INSTALLATION AND TUNING GUIDE FOR: EMS P/N 30-6905 EMS-4 PROGRAMMABLE ENGINE MANAGEMENT SYSTEM WARNING: ! This installation is not for the tuning novice nor the PC illiterate! Use this system with EXTREME caution! The EMS-4 allows for total flexibility in engine tuning. Misuse of this product WILL destroy your engine! Installation of the EMS-4 must be performed by a qualified EFI technician familiar with EFI sensors, actuators and wiring. You should also visit the AEM EMS Tech Forum at http://www.
Revision History Version Initial Release, 1.0 1.1 1.2 Date Modified Sections 12/27/10 12/28/10 Typical Idle Setup Tab Injectors section 12/28/10 Injection Phasing Coil Phasing 1.3 12/30/10 EMS-4 GPIOs 1.4 1/4/11 1.5 1/10/11 Timing Pattern Basics Various 1.6 1.
Table of Contents General Information ...................................................................................................................... 6 Electronics Warranty ..................................................................................................................... 6 Part 1 – EMS-4 Installation ........................................................................................................... 7 EMS-4 Basic Specifications ...............................................
Part 3 – Tuning Guide ................................................................................................................. 98 Background ............................................................................................................................. 98 Fuel Tuning General Concepts ............................................................................................ 98 Spark Tuning General Concepts ..............................................................................
Fuel Tuning ........................................................................................................................ 158 Acceleration/Deceleration Modifiers for Engine Fueling .................................................... 176 Ignition Tuning Theory ....................................................................................................... 182 Ignition Map .......................................................................................................................
General Information READ AND UNDERSTAND THESE INSTRUCTIONS BEFORE ATTEMPTING TO INSTALL THIS PRODUCT. VISIT THE AEM PERFORMANCE ELECTRONICS TECH SUPPORT FORUM AT http://forum.aempower.com/forum/index.php ALL CURRENT SOFTWARE AND DOCUMENTATION IS AVAILABLE ON THIS FORUM. YOU MAY ALSO CONTACT AEM PERFORMANCE ELECTRONICS TECH SUPPORT AT 1-800-4230046 IF YOU HAVE ANY QUESTIONS. Electronics Warranty Advanced Engine Management Inc.
Part 1 – EMS-4 Installation EMS-4 Basic Specifications EMS-4 Specifications CPU Core: Injector Drivers: Coil Drivers: GPIO Pins: O2 Sensor Input: Timing Sensor Inputs: Knock Sensor Input Throttle Position Input Manifold Pressure Sensor Coolant Temperature Sensor Inlet Air Temperature Sensor USB CAN Sensor Ground 5 Volt Reference 16 bit / 40 MHz 4 x Saturated (8 ohm minimum, High Impedance Only) 4 x 0-5V Falling Edge Fire (do not connect directly to coil primary) 4 x 1.
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Two partially assembled harness options are available for the EMS-4: 1. P/N 30-2905-96 EMS-4 Full Harness 2. P/N 30-2905-0 EMS-4 Mini Harness Photographs and schematics for each are shown above. The Full Harness option is best suited to applications where no factory harness exists or where modifications are so extensive, it is easier to build a custom harness. This harness includes a fused power distribution center with main relay. All circuits are pre-terminated at the ECU connector.
Using a sharp pick or probe, push in on the locking tabs holding the outer retainer. Remove the retainer. Page 11 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Use pick to pry open the retaining tabs holding the backshell halves together. Open the shell to expose the cavities. Page 12 of 279 EMS-4 Install and Tuning Guide_Rev 1.
To remove a terminal, carefully pry up on the retaining clip. Be careful as the clips can break if bent too far. To add a new circuit, insert the terminal from the back as shown until it clicks into place. Page 13 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Showing terminal fully seated. Following is the proper tool for use with the Delphi Micro Pack terminals used in the ECU main connector. Delphi Part No: 12070948 Application: Unsealed Micro-Pack 100, Female only Core and Insulation Cable Range (mm2): 2.0-0.35 Page 14 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The tool is available in many places. One is shown below. Web address – http://www.mouser.com AEM recommends using the proper tool for all ECU terminations. Image shows a properly crimped terminal. Top View. Page 15 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Side View. After crimping, be sure to do a pull test to make sure the terminal is properly installed. Electronic Wiring Conventions A proper wiring job includes proper termination of the wire at the sensor. The wire terminal end must be moisture tight where it plugs into the sensor and it must have strong, electrically sound terminals. The preferred method of securing a wire to a terminal is to use a crimp terminal with NO solder.
The routing of the wire loom is critical to EFI system performance and safety. The following safety considerations should be made when installing the wire loom: Heat protection: the loom should be placed away from or insulated from sources of heat. The obvious item(s) that should be avoided are the exhaust manifolds, EGR delivery tubes, and turbochargers. If it is absolutely necessary to route a wire in close proximity to any of these items, then a suitable insulator must be used.
Noise can be caused by the electric motor in a fuel pump, which if connected directly to the ECU, may feed back into the circuit board ground plane. In the case of a fuel pump, the typical amperage required to run the pump is 10A or more depending on its size. The driver in the ECU that sends the command to run the fuel pump is only capable of supplying 1.5A, and clearly this type of load on the driver would cause it to burn out.
A high quality over-molded termination is included for USB communications. Plug one end of a standard USB extension cable (included) into the harness connector and the other end into an open USB port on the PC. Communications is possible only when the EMS is powered up. CAN Connector CAN Connector A compact pre-terminated connector is included for use with AEM CAN enabled devices. Injectors Injector Basics A fuel injector is a valve that can be opened and closed very quickly.
((Power x BSFC) x (1 + Safety Margin))/Number of Injectors = pounds/hour An example of this equation is: 6 CYL. engine rated at 500 hp on gasoline using moderate boost with a 15% safety margin on the injector 500 x .625 = 313 lbs/6 = 52 lbs/hr/ injector. 52 x 1.15=60lbs/hr/ injector If we take the flow of the injector (60 lbs/hr) and multiply it by the number of cylinders (6), we arrive at a total of 360 lbs/hr of flow.
AEM kit P/N 30-2020 (Optional) Bosch Style Injector Connector Kit contains the parts to assemble 4 injector connectors. The kit contains Four Bosch style female injector connectors and 10 contacts (2 extra contacts are included for spares). IMPORTANT! The contacts are “Pull to Seat” meaning you must feed the wire through the connector housing BEFORE you crimp on the contacts. The wire is then pulled back into the housing and the contact locks in place.
engine position. Distributed spark systems also rely on a mechanical link between the engine and ignition output, which adds another dimension of unreliability-and to a minor extentinaccuracy in timing. In addition to these problems, distributed spark systems typically produce the least intense spark of all ignition systems. The time to achieve full charge diminishes as engine speed increases; therefore the coil charge is reduced as a function of RPM.
Coil 3 Output Coil 4 Output Fused Coil Power Coil Ground 22 22 14 14 Dk Blue Dk Blue Red Black IGN 3 IGN 4 COIL PWR PWR GND Warning! - The ignition outputs from the EMS-4 are not designed to trigger an ignition coil directly. Connecting them to a coil that does not contain a built-in driver will damage the EMS-4. Coils without built-in drivers typically have only two pins on the connector. Coils with built-in drivers typically have 4 or more pins on the connector.
AEM Four Channel Coil Driver P/N 30-2840 Four Channel Coil Driver Connections Coil Driver Connections Coil Driver ECU Coil 1 Output ECU Coil 2 Output ECU Coil 3 Output ECU Coil 4 Output Ground Coil 1 Negative Terminal Coil 2 Negative Terminal Coil 3 Negative Terminal Coil 4 Negative Terminal Connect to EMS-4 harness, IGN 1 EMS-4 harness, IGN 2 EMS-4 harness, IGN 3 EMS-4 harness, IGN 4 EMS-4 harness, PWR GND Coil 1 Negative Terminal Coil 2 Negative Terminal Coil 3 Negative Terminal Coil 4 Negative Termina
IGNITION OUTPUT FROM EMS TO COIL DRIVER OR CDI DWELL 5V FALLING EDGE FIRE DWELL GND IGNITION OUTPUT AFTER COIL DRIVER DWELL RISING EDGE FIRE DWELL 12V GND Signal comparison – before and after coil driver Page 25 of 279 EMS-4 Install and Tuning Guide_Rev 1.
TPS (Throttle Position Sensor) Harness Connections TPS Harness Connections Name +5.0 volts, Vcc Throttle Position Sensor Sensor Ground Wire 22 22 22 Wire Color Red White Black Stamping VCC THROTTLE SIG GND VCC – Connect to sensor 5 volt reference THROTTLE – Connect to sensor signal SIG GND – Connect to sensor ground MAP Sensor Harness Connections MAP sensor harness connections Name +5.
AEM P/N 30-2130-75 “MAP Sensor Kit, 5 BAR” Typically used to measure intake & exhaust back pressures. Air Temp Sensor Harness Connections Air Temperature Sensor Harness Connections Name Inlet Air Temp Sensor Sensor Ground Wire 22 22 Wire Color White Black Stamping AIR TEMP SIG GND AIR TEMP – Connect to sensor signal SIG GND – Connect to sensor ground AEM P/N 30-2010 (Optional) Air Temp Sensor kit is specifically designed for temperature measurements in automotive systems.
Water Temp Sensor Harness Connections Water Temperature Sensor Harness Connections Name Coolant Temp Sensor Sensor Ground Wire 22 22 Wire Color White Black Stamping COOLANT SIG GND COOLANT – Connect to sensor signal SIG GND – Connect to sensor ground AEM P/N 30-2011 (Optional) Water Temp Sensor kit is specifically designed for temperature measurements in automotive systems. The kit contains One GM style temperature sensor, one “6” Flying Lead” mating connector assembly and a weld in aluminum bung.
Crank Sensor Crank Sensor Basics The crank sensor is used to calculate engine speed, ignition timing and injection phasing angles. It senses a toothed wheel (reluctor wheel, reluctor ring, etc.) and converts this pattern into a voltage/frequency signal that the EMS uses for basic calculations. Either on its own, or combined with the cam position sensor, it is the most important input to the system. There are two basic types of crank sensors, variable reluctance (VR or “mag”) and hall-effect.
Hall Effect voltage signal The internal circuitry on the EMS is different depending on what type of sensor is being used. Note that there are two different inputs on the EMS for crank and cam position. One for a Hall Effect type pickup. The other for a VR or “mag” pickup. The EMS-4 crank sensor VR inputs go through a signal conditioning chip on the circuit board that converts the raw (zero crossing) signal into a clean 0-5V square wave signal as shown below.
Shows signal conditioning with edge invert on typical “missing tooth” style VR crank sensor pattern Internal Signal Conditioning Example Page 31 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Shows signal conditioning with edge invert on typical evenly spaced VR crank pattern. Internal Signal Conditioning Detail All VR Crank Sensor inputs to the EMS-4 must be connected such that the rising edge of the raw sensor signal is the consistent zero crossing edge as shown in the examples above. Failure to do this could result in misfires or ignition timing inaccuracies. Verify data with an oscilloscope or contact your sensor manufacturer to verify polarity.
Harness Connections Crank Sensor Harness Connections Crank Sensor Ground Crank Sensor Mag Input Crank Sensor Hall input +12 volts Cable Shield 28 28 24 24 --- White Green Black Red Crank Sensor Mag Input, Green – Connect to VR (+) signal (rising edge zero cross). Not used for Hall sensor configurations. Crank Sensor Hall input, Black – Connect to Hall sensor signal. Not used for VR sensor configurations. +12 volts, Red – Connect to Hall sensor reference voltage. Not used for VR sensor configurations.
Cam Sensor Input Cable End Harness Connections Cam Sensor Harness Connections Cam Sensor Ground Cam Sensor Mag Input Cam Sensor Hall +12 volts Cable Shield 28 28 24 24 --- White Green Black Red Cam Sensor Mag Input, Green – Connect to VR (+) signal (rising edge zero cross). Not used for Hall sensor configurations. Cam Sensor Hall, Black – Connect to Hall sensor signal. Not used for VR sensor configurations. +12 volts, Red – Connect to Hall sensor reference voltage.
The vehicle speed sensor must be a hall-effect device. It is used to detect wheel speed for use in various EMS-4 software functions. Harness Connections Vehicle Speed Sensor Harness Connections Name VSS Ground VSS Hall Input +12.0 volts Wire 22 22 22 Wire Color Black White Red Stamping PWR GND VSS PWR PWR GND – Connect to vehicle speed sensor ground pin. VSS – Connect to vehicle speed sensor signal pin. PWR – Connect to vehicle speed reference voltage pin.
Fuel Pump and Idle Air Control Example Circuits DO NOT CONNECT DIRECT TO BATTERY The example above shows proper wiring design for inductive loads like fuel pump relays and idle air control/boost control solenoids. Note that simple on/off type outputs from the EMS-4 can be connected to any GPIO output but Pulse Width Modified (PWM) circuits such as those used for idle control or boost control must be connected to GPIO 5 – 8, pins 14 – 17 on the 36 way ECU connector.
Part 2 – AEM Tuner Software Installation All current AEM Tuner software installations are available for download from the AEM Performance Electronics Forum at: http://forum.aempower.com/forum/index.php All Software Downloads Link Click on the All Software & Firmware Downloads forum. Software Downloads Link Next click on the AEM Performance Electronics – All Software & Firmware Downloads forum Software Downloads Link Next click on the link shown above to reach the official download page.
Software Installation Revision Notes Example All current software releases will include a set of revision notes describing feature changes or additions since the last update. Page 38 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Software Installation Instructions Follow the Installation Instructions as outlined above. After the software installation is complete, click on the AEM Tuner icon to launch the application. AEM Tuner Shortcut AEM Tuner When AEM Tuner launches, the application will begin with a window similar to the one below: Page 39 of 279 EMS-4 Install and Tuning Guide_Rev 1.
AEM Tuner Environment Basic Terminology Calibration File – The calibration file is what the tuner modifies and will be specific to the engine setup. Options – Single values that are set by the user to change the operation of an EMS. Channels - Channels are data for viewing and logging. They are a window to the engine. They tell you everything the engine is doing and what all of the sensors are seeing. This window is one of the most valuable tools in helping to tune the engine.
Item Explanations - Item Explanations provide a brief description of what the currently selected in the currently selected Display does, or is used for. So, for example, if the selected Display was an Options Display, the Item Explanation would describe the selected Option with that selected Options Display. For Calibration items (Options and Tables) this explains how the ECU uses that item to accomplish a function. For Log items (Channels) this explains what the value represents to the ECU.
Menu Items Following is a basic description of each menu function. FILE Open Calibration - Opens a previously saved calibration file Open Last EMS Calibration – Opens the last calibration file saved in memory Open Recent Calibration – Displays a list of recent opened calibrations files. Choose one to open. Save Calibration – Saves currently loaded calibration file with the same file name. Only active when a calibration file is loaded.
Close Calibration – Closes the currently loaded calibration file. Calibration Notes – Allows the user to enter text that describes the calibration file. Calibration Notes Workspace File-Workspace Page 43 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Workspace – Open – Opens a previously saved workspace file. Workspace – Open Recent – Displays a listing of recently opened workspace files. Workspace – Save – Saves the current workspace file under the same filename. Workspace – Save As – Saves the current workspace with the option of choosing a new filename. Workspace – New – Creates a new blank workspace. Exit – Closes the AEM Tuner application. EDIT Edit Menu Undo - Undoes the last change made to the loaded calibration.
DISPLAY Display Menu Display Explorer – Opens a separate window where the user can select options, channels, tables or maps for use in the current tab. Browse through the list of available displays and double click on one to add it to the current tab. Display Explorer Page 45 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Show Options Full List Display – Opens a display that contains all available options for the current calibration type. Used for internal AEM diagnostics only. Show Coils Display – Opens a display that contains selections for activating and configuring ignition coil outputs. Coils Display Show Injectors Display – Opens a display that contains selections for activating and configuring injector outputs. Page 46 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Injectors Display Auto Arrange Displays – Automatically organizes the displays within the current tab so that none are overlapping. Restore Displays – Restores the workspace settings back to the previously saved settings. TABS AEM Tuner Tabs The Tabs menu item lists all currently saved tabs screen templates. Right clicking in the tab area of the menu space shown above will bring up the following menu: Page 47 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Tabs Menu New tabs can be created. Existing tabs can be renamed hidden or deleted. Currently hidden tabs can be displayed for re-use and all tab properties can be modified by selecting the Property item. Tabs Menu Detail Tabs are saved as part of the Workspace configuration. Remember to save the workspace to retain your changes. Page 48 of 279 EMS-4 Install and Tuning Guide_Rev 1.
ECU EMS Menu Connect to ECU – Instructs AEM Tuner to attempt a communications connection with the EMS hardware. Disconnect – If connected, instructs AEM Tuner to close the communications connection with the EMS. Upload Calibration – Loads a new calibration file into the EMS. Page 49 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Upload Calibration Dialog Click the Browse button to select a calibration file. Note that the calibration firmware version must match the EMS firmware version. The current EMS version is displayed at the top of this window. An optional check box labeled Download EMS‟s Calibration First allows the currently loaded calibration file to be saved prior to loading the new one. When the desired calibration file is chosen, click on the Go button to load it into the EMS.
Set Password Dialog Clear EMS Calibration – Clears the currently loaded calibration from EMS memory. Upload EMS Firmware – Allows the user to update the EMS firmware to the most current revision. Follow the on-screen instructions to complete the upgrade. Note that a new calibration compatible with the new firmware version is required to complete the process. Clear EMS Firmware – Clears the currently loaded firmware version. Follow the on-screen instructions to complete the process.
EMS Connection Preference Dialog LOGGING Logging Menu Start PC Logging – (F6 Hotkey) will log data from all channel displays in the active tab. Cancel PC Logging – (F8 Hotkey) will stop logging and discard the file. Stop and Save – (F7 Hotkey) will stop logging and prompt the user to save the logged file. EMS Internal Logging Setup – Opens a dialog window that allows the user to configure the internal logging settings of the EMS. Page 52 of 279 EMS-4 Install and Tuning Guide_Rev 1.
EMS Internal Logging Setup Dialog Logging Conditions Logging Conditions – Defines the activation criteria for the internal logging function. Logging is Off – Internal logging function is disabled. Logging is Always On – When the EMS is powered up, the logger is logging. Page 53 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Logging is on when engine is running – When engine speed is greater than 0, data will be logged. Logging is on when the vehicle is moving – When the vehicle speed is greater than 0, data will be logged. Note that this setting requires a properly configured vehicle speed sensor. Logging is on at full throttle – Data will be logged at wide open throttle only.
Internal Logging Memory Control Select Loop Logging to continue logging after all memory is used. Only the oldest data will be lost when the log loops. Use the slider to select the logging rate. The rate, channels selected and EMS logging memory capacity will be used to estimate the log run time. Download EMS Log Menu Item Download EMS Log – Select this item when connected to the EMS to download the current logged data file. Open AEMLog – Select this item to Open AEMLog data analysis software.
TOOLS Tools Menu Configure Output Dialog – Used to define the activation criteria for EMS configurable outputs. Configure Outputs Dialog Page 56 of 279 EMS-4 Install and Tuning Guide_Rev 1.
GPIO General Purpose Activation To activate an output for a General Purpose Function, double click on the output function row/column cell adjacent to the output name as shown. Select General Purpose from the drop down list then hit the ENTER key to confirm. Output Activation Criteria Under Pin Configuration, check the Enable Pin box to activate the output. The Switch Input drop down selection allows the user to select a switch input to manually activate the output.
the output to activate. To control the output using only the pin conditions, select Ignore Switch Input and set the activation conditions as needed. In the example above the following conditions must be true for the output to turn on: RPM greater than 0 Engine Load greater than -14.
Compare - Open File Window Calibration Compare Dialog The tool will allow the user to choose and copy selected options, tables or maps values from the “Compared Calibration” to the currently opened calibration. Compare Calibration Detail Page 59 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The tabs at the top of the window allow the user to select between different types of data, options, tables or maps. To copy a value, highlight it and click Copy Selection. Alternatively, all items can be copied at once by clicking the Copy All button. Convert Current Calibration Tool – Will convert a calibration created in one EMS version to another EMS version. Calibration versions must match the version of software installed in the EMS. Software installed in the EMS is also referred to as firmware.
Configure Conversion Dialog The first step is to choose the EMS version to convert the current opened calibration into. There are two different types of conversions, Auto and Manual. Manual conversions are usually for internal AEM use but these can also be accomplished by experienced users as well. Auto conversions employ a conversion script provided with the new firmware release. The conversion script simplifies the process limiting the number of decisions the user must make during the conversion process.
Tools - Preferences Menu Item Unit Preferences The first preference category allows the user to select their preferred units. This selection defines what units will be used in channel displays and logged data for each type. Unit Preferences Detail The right hand column in this dialog includes drop down selection lists. Left click to activate the drop down then select from the list. Page 62 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Display Preferences The display preferences dialog includes basic color and font preferences for use in AEM Tuner. Experiment to find what works best. This dialog also includes preferences for Live Tracing. Live Tracing is used in maps to graphically highlight the areas of the map the EMS is accessing at any given point in time. This is only active when the EMS is powered up and connected to the PC. Page 63 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Hotkey Preferences Hotkeys are time saving tools and are extremely useful. The Hotkeys preference dialog allows the user to have complete control over the Hotkeys defined for almost any action. Many standard Hotkeys are pre-defined. All can be modified by the user.
Logging Preferences There are two types of logging, Internal Logging and PC Logging. The system can be configured to always log to the PC when the PC is connected to the EMS by selecting the first checkbox in the window above. The second checkbox allows the user to always delete the log file saved internally to the EMS after downloading. Otherwise, a copy is downloaded and the original is retained in EMS memory. Standard log file names for both types of logging can also be configured in this window.
Calibration Edit Preferences When the first checkbox in the window above is selected, the ENTER key must always be pressed to confirm calibrations changes. This is the default configuration. The Auto-Rescale selection allows AEM Tuner to continuously optimize the resolution in the main fuel map and crank injector time table. Default setting for this selection is ON. Page 66 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Quick Tune Preferences The quick tune feature allows AEM Tuner to automatically calculate main fuel map changes necessary to minimize the O2 correction value. Page 67 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Application Preferences The application preferences dialog controls settings related to Workspace, Calibration Files and Tabs loading. It also allows the user to enable or disable the application updates feature. When the Check for Application Updates at Startup is selected, AEM Tuner will connect to the internet and notify the user of software or calibration file updates from AEM. Page 68 of 279 EMS-4 Install and Tuning Guide_Rev 1.
WIZARDS Wizards Menu Item Setup Wizard – Contains pre-defined options, tables and maps to configure a calibration file for a certain purpose. Applying a Setup Wizard modifies the currently opened calibration file. Setup Wizards can be used to apply the proper battery offsets for fuel injectors or select the proper settings for a certain manifold pressure, air temperature or coolant temperature sensor. AEM is constantly adding to the list of available Setup Wizards for each EMS type.
Setup Wizards To use a Setup Wizard, select a Wizard type then either double click on the desired settings or click once and hit the Apply button. In addition to the generic Setup Wizard shown above, there are several specific Wizards used to accomplish certain tasks. Set Throttle Range Wizard – The useable range for the TPS sensor must be defined in the calibration file accurately. The Set Throttle Range Wizard automates this process. Set Throttle Range Wizard The PC must be connected to the EMS.
Ignition Timing Sync Wizard – The purpose of the Timing Sync Wizard is to synchronize the actual ignition timing with the value commanded by the EMS. Ignition Timing Sync Wizard The PC must be connected to the EMS and the engine must be running. To minimize ignition timing fluctuation, the timing from the EMS can be locked at a given setting. Select or type in a value then click the Lock Ignition Timing at checkbox.
Change Injector/Pressure Wizard Enter the original (old) injector size and pressure setting and the new settings. AEM Tuner will automatically adjust the calibration to account for these changes. Configure Gear Ratio Wizard – The gear ratio can be calculated based on a ratio of engine speed to vehicle speed. Once the gear ratio is calculated, the data can be used to define a gear position table based on calculated gear ratio. This wizard automates the process.
Configure Gear Ratio Wizard The EMS must be powered up and the PC must be connected. WARNING! This procedure should be completed on a chassis dynamometer to ensure safety. The driven wheels must be rotating to generate a suitable vehicle speed signal. Follow the on-screen instructions. Select Engine Speed for GearCal Spd 1 and Vehicle Speed for GearCal Spd 2. Note that certain plug and play applications may have different settings but these will be pre-configured in the base calibration.
To use the wizard, enter the number of primary and secondary injectors, the flow rate of each (as measured in the same units) and the stoichiometric ratio of the fuel used for each. Click the OK button to complete the process. Note that there are still certain settings necessary to completely define a staged injection setup. These will be covered later in this manual. LIVE TRACING Live Tracing Menu Page 74 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Live Trace Main Fuel Map showing Live Tracing The Live Trace features displays a brief “history” of where the EMS has been accessing tuning data from a map. Stop Live Tracing – Stops Live Tracing if currently running. Clear Live Tracing – Clears the current Live Trace saved in Memory. Show Live Tracing – Displays the currently saved Live Trace. Toggle Live Tracing Mode – Toggles between the two available Live Tracing modes, auto fading with trail length or no fading.
Program Guide – Opens the on-line help file. Check Updates – If connected to the internet, AEM Tuner will contact the AEM servers and download any available software or calibration file updates. AEM Tuner Updates Feature Click the Download and Install button to save the files. Calibration file updates are automatically saved in the AEM Updates folder as shown below: Page 76 of 279 EMS-4 Install and Tuning Guide_Rev 1.
About AEM Tuner – Displays the installed version and build date: Editing EMS Calibration Files Editing Options Displays Options can be any of the following: 1. Single numeric values like Fuel Pump Prime time in seconds 2. On/Off selections to enable or disable calibration features 3. Drop down list selections to assign an input pin or output pin for use in a calibration feature or function.
Choose new option from drop down list. Option will be inserted after highlighted row. Move selected option row up or down within the display window. Removes currently selected option from display. Change display contents. Opens separate window below: Selected Options Available Options Page 78 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Select options from the left side then click OK to add them to the display. Options can also be selected from a “Tree” type view by clicking on the Tree tab above. Reset selected modification states. For any currently highlighted option row, clicking this button will reset the state of the selected option. Reset all states. Resets all modification states within the option window. Page 79 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Options Display – Right Click Menu Right clicking within an option display brings up the menu above. Functions are similar to those described above using the toolbar icons. Editing Options Display Data To edit a value within the options display window, first double click on the value until it is highlighted blue as shown above. At this point, function is similar to any standard Windows text box. Edit the value and hit the ENTER key to confirm.
Editing 2D Table Displays A 2D table represents a function that equates one value to another. AEM EMS calibrations contain many 2D tables. Examples include sensor calibration tables that equate voltage to temperature, tables that define desired idle speed as a function of coolant temperature, etc. 2D table in Graph View mode 2D table in Table View mode Table Display Toolbar Icon Function Show or hide the icon toolbar Close display Reset all states. Resets all modification states within the table window.
Reset selected modification states. For any currently highlighted cell, clicking this button will reset the modification state of the selected cell. Toggles table view mode Toggles graph view mode Toggles split graph/table mode Auto table sizing. Allows table cells and data to expand to fit current window size. Font table sizing. Maintains table font size specified in Tools – Preferences – Display – Font. Follow ECU. Selected cell or cell group will follow the table cursor while live tuning.
To modify table data, left click and drag to select the cells you want to change. Add or subtract from the existing value using the + and – keys. Holding the CNTRL key down will create larger changes. Table Editing with Right Click Menu Percent Change – (hotkey E) applies a percentage offset to the value(s). Note that the percentage calculation type is a user preference. Set Value – Replaces the existing value(s) with the new one entered.
interpolation (either horizontal or vertical) to determine a linear slope, then changes the values of all the cells in between so they have the same slope. Before Interpolation: Highlighting Cells to Interpolate: Page 84 of 279 EMS-4 Install and Tuning Guide_Rev 1.
After Interpolation: Other Editing Options: There are four other automatic editing options: Linear Extrapolate (left or right) - Extends the slope of the first two selected cells to the rest of the cells selected in the interpolation direction. Flatten (left or right) - Allows the user to assign to a group of selected cells the value of the first cell in the flatten direction. Page 85 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Before Linear Extrapolation: Selecting Cell Range to Extrapolate: Page 86 of 279 EMS-4 Install and Tuning Guide_Rev 1.
After Extrapolation: Before Flattening: Page 87 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Selecting Cells to Flatten: After Flattening Right: Page 88 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Editing Channel Displays Channel Display Toolbar Icon Function Show or hide the icon toolbar Quick insert new channel Move selected channel row up or down within the display window. Removes currently selected channel from display. Change display contents. Opens separate window below: Add or subtract channels by selecting them in left column. Click OK to confirm. Tree view is also available by clicking the Tree tab. Configure channel properties.
Select the desired channel then click the column next to each property to edit the settings.
Show or hide the icon toolbar Close display Reset all states. Resets all modification states within the map window. Reset selected modification states. For any currently highlighted cell, clicking this button will reset the modification state of the selected cell. Toggles table view mode Toggles graph view mode Toggles split graph/table mode Toggles horizontal view orientation. Only available in split graph/table mode Toggles vertical view orientation.
Split graph/table mode (vertical orientation): Auto table sizing. Allows map cells and data to expand to fit current window size. Font table sizing. Maintains map font size specified in Tools – Preferences – Display – Font. Follow ECU. Selected cell or cell group will follow the map cursor while live tuning. With this feature turned on, tune with the +/- keys live and be sure you are editing the exact location used by the ECU. Manual selection. Selected cells are independent of live cursor position.
Highlighted area selected: User definable 3D positions. Set map to desired view orientation then right click over each of these buttons to select up to 3 default 3D orientations. Manual Editing with +/- Keys Highlighted area increased using the + key Note: Display color preferences and orientation changed to illustrate variations Page 93 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Automatic Editing with Right Click Menu Right click menu editing options for 3D maps are similar to those for the 2D tables but there are more of them.
Before horizontal interpolation. Area of interest highlighted. After horizontal Interpolation. Vertical interpolation results similar but in vertical direction. Interpolate Both will affect both directions Page 95 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Before linear extrapolate right. Area of interest highlighted. After linear extrapolate right. Linear extrapolate left results similar but in opposite direction. Up and down affect also similar. Page 96 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Before flatten right. Area of interest highlighted. After flatten right. Flatten left, up and down results are similar. Page 97 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Part 3 – Tuning Guide Background What is “Tuning”? Tuning can mean anything from adjusting the idle mixture screw on your carburetor to experimenting with custom length headers for your engine to setting up the flow ratio between primary and secondary injectors for your EFI calibration. Tuning covers a wide range of topics and not all are related to fuel injection.
Spark Tuning General Concepts The ignition timing or spark timing value refers to the distance in crank degrees between the spark plug firing event (initiating combustion) and the uppermost point of the pistons stroke (top center TC, top dead center TDC, etc.) If the start of the combustion process is progressively advanced before TC, the compression stroke work transfer (which is from the piston to the cylinder gases) increases.
Calibration Setup Base Calibrations There are several base calibrations that can be used as a starting point. They are installed with the software and located here: C:\Program Files\AEM\AEMTuner\Calibrations\AEM Updates\EMS4 AEM is constantly adding to, updating and improving the base calibration library. Go to the File menu and select Calibration Notes… for information on each file. Example shown below: Page 100 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Timing Pattern Basics Page 101 of 279 EMS-4 Install and Tuning Guide_Rev 1.
When the “teeth” on a toothed wheel pass by a sensor, the sensor creates a voltage pattern that is used by the ECU for many important calculations. The example above shows two different toothed wheels, one that rotates with the crankshaft. The other rotates with the camshaft (1/2 engine speed). Representative voltage signal patterns for one complete engine cycle (2 revolutions) are also shown. The calibration file must contain the proper settings to define this pattern for the ECU.
The following Sync Setup options are used in this example: Fuel Teeth = 24, Defines how many significant crank teeth edges are to be used for fuel injector phasing calculations. Spark Teeth = 24, Defines how many significant crank teeth edges are to be used for ignition coil output phasing calculations. Wheel Teeth = 24, Defines how many significant teeth are expected during one engine revolution. Used for engine RPM calculation.
The tooth control table has many different functions. The most basic of which is to tell the ECU what to do when it sees a significant edge on the crank sensor input. The values are plotted versus “A Tooth”. The A Tooth count will increment on every edge the pattern. In more complex situations, the table can be used as a translator to convert a complex pattern into a common evenly spaced pattern of 24 fuel teeth per cycle as shown in the examples above.
Injector phasing is defined in the window above. Injector Name – The injector output. See application pinout sheet or schematic for more information. Active – Enables or disables an injector output. Note that a power cycle is necessary after making changes to these settings. Knock Sensor #1 – Assigns an injector to a knock sensor input. Fuel changes defined in the knock control function will be applied according to these settings. The number of knock sensor inputs varies by application.
Some tuners may want to connect injector output #1 to cylinder #1, injector output #2 to cylinder 2, etc. The example above shows how this configuration would be defined assuming the engine firing order is 1 – 3 – 4 – 2. Injector Advance Table The Injector Advance table controls the timing of the injection events. The units are in crank degrees and are vs RPM breakpoints. Range is -360 to +360 degrees from the first crank tooth after synchronization.
The sync strategy takes advantage of the missing tooth sections of the trigger wheel. Missing – Tells the EMS to look for 2 missing crank tooth edges. MX Sync Test – Must be set to the number of normal crank tooth edges between missing edges. In this case there are 57 (really 58 but the first edge is counted as a zero) MX Time – Multiplier used internally by the EMS to define the “missing tooth window” Sync Teeth – Defines the number of cam sync edges between missing crank edges.
Basic ignition phasing settings are similar to those for the fuel injectors. Referring again back to our example above, there are 4 ignition outputs that fire sequentially spaced 180 crank degrees or 6 teeth apart. Coil Name – The coil output. See application pinout sheet or schematic for more information. Coils #1B – #4B are paired outputs for Coils #1 - #4. In other words, they are the same output but each firing event can be phased and trimmed independently of the other.
Alternative setup – Coil outputs fire in “Cylinder Firing Order” Like the injector phasing example above, some may want to connect coil output #1 to cylinder #1, coil output #2 to cylinder 2, etc. The example above shows how this configuration would be defined assuming the engine firing order is 1 – 3 – 4 – 2. Page 109 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Dwell Discussion The diagram below illustrates a basic inductive ignition system setup with four independent ignition outputs (Coils 1 – 4). Page 110 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Transistors serve many functions but in this case they are applied as Power Drivers. The input circuit to the transistor from the ECU requires very little current flow to turn the transistor ON. When the transistor is ON, a high current capacity path is created between the coil negative terminal and ground. High current means more temperature to dissipate. A stand-alone ignition driver module or a driver module built into a coil assembly is designed to efficiently dissipate this heat.
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Coil dwell is configured in the EMS calibration using the following options and tables: Ignition Charge Time (ms) = (Dwell vs Battery V value) * (Dwell vs RPM value) Example: Calibration contains the following values: Dwell vs Battery V = 3.0 ms (at 13V) Dwell vs RPM = 100% (most RPM) Charge Time = 3.0 * 100% = 3.0 ms The Dwell Min and Dwell Max options are used to define the minimum and maximum allowed dwell time in units of teeth.
Set up RPM and Load axes The RPM (X) and Load (Y) axes of the 3D maps must be set up before any calibration work is to be done. The matrix for all 3D maps except the idle fuel and idle ignition maps is 23 (X) by 17 (Y). The set points may be linear or non linear. Most road cars with relatively mild tuning characteristics use linear X & Y axes. On engines that are modified with narrow power bands the non-linear set up is often used.
Non-Linear Load and RPM Setup EFI Sensors TPS (Throttle Position Sensor) The TPS determines the position of the throttle blade in the throttle body. This input is used to determine rate of throttle angle change (both positive and negative), idle position, and discrete throttle opening for TPS-based calibrations. The TPS typically is a potentiometer bolted to the end of the throttle shaft.
While on the subject of throttle opening we must caution you to make sure that full throttle is achieved by having someone verify that the throttle blade is opening fully and up against the stop on the throttle body while you depress the throttle. Also, make sure that nothing interferes with the full range of the throttle opening, such as a floor mat. MAP (Manifold Pressure Sensor) Before any discussion is held of what a MAP sensor is, it is necessary to understand what manifold pressure is.
We find it easiest to work with the accepted standard of kilopascals (kpa) of absolute pressure. It is important to know the relationships of the various nomenclatures of pressure. The units of pressure in use today are; 1 bar (b) = 100 kilopascals (kpa) = 14.5 psi = 29.529” Hg. 1 atm. = 101.325 kpa = 14.7 psi = 29.92” Hg = 1.01325 b Page 117 of 279 EMS-4 Install and Tuning Guide_Rev 1.
PSI Absolute 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 11.00 12.00 13.00 14.00 Kpa 6.89 13.79 20.68 27.58 34.47 41.37 48.26 55.16 62.05 68.95 75.84 82.74 89.63 96.53 Inches Hg 2.04 4.07 6.11 8.14 10.18 12.22 14.25 16.29 18.32 20.36 22.40 24.43 26.47 28.50 Bar 0.07 0.14 0.21 0.28 0.34 0.41 0.48 0.55 0.62 0.69 0.76 0.83 0.90 0.97 Pressure Gauge -27.89 in Hg ↓ -25.86 -23.82 -21.79 -19.75 -17.71 -15.68 -13.64 -11.61 -9.57 -7.53 -5.50 -3.46 -1.43 14.70 15.00 16.00 17.00 18.00 19.00 20.00 21.00 22.
The MAP sensor provides manifold pressure information to the ECU for calibration based on MAP vs. RPM. The MAP information is used in both the fuel and ignition Y-axis of their respective maps. On racing engines that use individual runner manifolds, a TPS based fuel map can be used while the ignition can be MAP based. This is desirable because the ignition should always be load based to provide knock free operation. A MAP sensor reads in absolute pressure, just like the name implies.
Water Temp Sensor The coolant temperature sensor (CLT) is a variable resistance thermistor (thermal resistor) that sends a return voltage back to the ECU based on the temperature of the engine coolant. This sensor can also be used for virtually any other type of automotive fluid if it is located in that liquid‟s respective reservoir. Unlike other types of sensors that emit voltage signals to the ECU, with CLTs the ECU outputs a +5V signal to the CLT and the sensor‟s resistance determines the return voltage.
Typical production vehicle oxygen sensors rely on “Nernst Cell” technology, commonly called “Narrow Band” and sometimes erroneously described as “Wide Band”. This is a very cost effective method that outputs a voltage based on the oxygen content of the gas being sampled. It is accurate in the region surrounding stoichiometric operation and leaner. Unfortunately, in the rich region where high performance engines usually operate, their accuracy and repeatability is virtually non-existent.
BOSCH LSU4.2 UEGO Sensor UEGO Gauge & RED: 12V Power Controller BLACK: Chassis Ground WHITE: 0-5V Output BLUE: Serial Output The following is a chart of typical AFRs. Note that every engine is different and this may not be the optimum set up for your particular vehicle. The AFRs on this chart are very conservative to minimize the potential for engine damage. These AFRs depend on the condition that ignition timing and fuel octane are adequate enough to prevent knocking.
Naturally Aspirated Piston Engines W/ Pent roof Combustion Chamber Air/Fuel Ratio 13.0:1 13.0:1 L 100 13.0:1 13.0:1 13.0:1 13.0:1 12.8:1 12.8:1 O 90 13.5:1 13.5:1 13.5:1 13.5:1 13.5:1 13.5:1 13.5:1 13.5:1 A 80 14.0:1 14.0:1 14.0:1 14.0:1 14.0:1 14.0:1 14.0:1 14.0:1 D 70 14.0:1 14.2:1 14.2:1 14.2:1 14.2:1 14.2:1 14.2:1 14.2:1 60 14.0:1 14.7:1 14.7:1 14.7:1 14.7:1 14.7:1 14.7:1 14.7:1 I 50 14.0:1 14.7:1 14.7:1 14.7:1 14.7:1 14.7:1 14.7:1 14.
Turbocharged Piston Engines W/ Pent roof Combustion Chamber Air/Fuel Ratio L 300 13.0:1 12.5:1 12.2:1 12.2:1 12.2:1 12.2:1 12.2:1 12.2:1 O 275 13.0:1 12.8:1 12.5:1 12.5:1 12.2:1 12.2:1 12.2:1 12.2:1 A 250 13.0:1 12.8:1 12.5:1 12.5:1 12.2:1 12.2:1 12.2:1 12.2:1 D 225 13.0:1 12.8:1 12.8:1 12.8:1 12.5:1 12.5:1 12.5:1 12.5:1 200 13.0:1 12.8:1 12.8:1 12.8:1 12.5:1 12.5:1 12.5:1 12.5:1 I 175 13.0:1 13.0:1 13.0:1 12.8:1 12.8:1 12.8:1 12.8:1 12.
Lambda to AFR conversion chart Lambda AFR Lambda AFR Lambda Lambda AFR AFR 1.3 19.03 1.14 16.69 0.98 14.35 0.82 12.00 1.29 18.89 1.13 16.54 0.97 14.20 0.81 11.86 1.28 18.74 1.12 16.40 0.96 14.05 0.8 11.71 1.27 18.59 1.11 16.25 0.95 13.91 0.79 11.57 1.26 18.45 1.1 16.10 0.94 13.76 0.78 11.42 1.25 18.30 1.09 15.96 0.93 13.62 0.77 11.27 1.24 18.15 1.08 15.81 0.92 13.47 0.76 11.13 1.23 18.01 1.07 15.66 0.91 13.32 0.75 10.98 1.22 17.86 1.
Sensor Calibration Calibrating Temperature Sensors There are several methods for calibrating temperature sensors for automotive systems. The most commonly used method is the Comparison Method which utilizes two sensors: one of unknown quality (the sensor of interest) and one of reference or standard quality. Both sensors are subject to the same temperature environment and the temperature is cycled over the range of interest.
Air Temp Analog Inpu(t) – Usually set to Air Temp Volts. Defines what pin the EMS expects to see the air temperature input on. Air Temp Fail Max – If the air temperature exceeds this value the input will be considered in fail mode and the EMS will set the value to Air Temp Failsafe. Air Temp Fail Min - If the air temperature falls below this value the input will be considered in fail mode and the EMS will set the value to Air Temp Failsafe.
Choose the air temperature setup from the list and hit the Apply button. This will modify the settings defined above for the chosen sensor. Please note that some amount of “fine tuning” to the calibration curve above may still be necessary especially if the EMS is installed in a “piggy-back” configuration with the factory ECU. Page 128 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Coolant Temperature Adjust the values in this curve until the coolant temp displayed in AEM Tuner matches the reference temperature throughout range. Coolant Analog Input – Usually set to Coolant Volts. Defines what pin the EMS expects to see the coolant temperature input on. Coolant Fail Max – If the air temperature exceeds this value the input will be considered in fail mode and the EMS will set the value to Air Temp Failsafe.
Choose the coolant temperature setup from the list and hit the Apply button. This will modify the settings defined above for the chosen sensor. Please note that some amount of “fine tuning” to the calibration curve above may still be necessary especially if the EMS is installed in a “piggy-back” configuration with the factory ECU. Throttle Position Sensor Calibration Set Throttle Range Wizard – The useable range for the TPS sensor must be defined in the calibration file accurately.
Set Throttle Range Wizard The PC must be connected to the EMS. With the throttle in the full closed position, monitor the TPS Volts value in the window above. Minimum TPS voltage is usually 0.5 – 1.0 volts. Click the Set TPS Volts Min button. Next push the throttle to the wide open position. Monitor the TPS Volts value. Maximum TPS voltage is usually 4.0 to 4.5 volts. With the throttle held open, Click the Set TPS Volts Max button. Close the window. The throttle is now calibrated.
vary based upon the MAP sensor used in the system. The load value of 0 displayed in AEM Tuner is determined by this setting. Map Max Volts - This is the value of the MAP signal in volts that corresponds with the maximum map value. This number represents high manifold pressure (full throttle on a naturally aspirated engine or boost on a forced induction engine). This number varies based upon the MAP sensor used in the system. The maximum load value displayed in AEM Tuner is determined by this setting.
Choose the MAP sensor setup from the list and hit the Apply button. This will modify the settings defined above for the chosen sensor. Page 133 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Fuel System Setup Fuel Pump Setup Any available GPIO pin can be used for the fuel pump control. Refer to the pinout sheet and schematic and choose an output pin. Go to the Tools menu item and select Configure Outputs to define the fuel pump configuration. Page 134 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Double click the Output Function column next to the chosen GPIO pin. Select Fuel Pump. Activate the Enable Pin checkbox. Be sure the Switch Input is set to Ignore Switch Input. Pin conditions must be set such that they are met all the time. Define the required Fuel Pump Prime setting. At key on, the fuel pump output will activate for this amount of time then shut off if no engine RPM signal is detected. Fuel Pump Sizing To achieve proper fuel delivery, you must select the right fuel pump for your vehicle.
(Power x BSFC) x (1 + Safety Margin) = pounds/hour Pounds/hour / 7.25 = gallons/hour. An example of this equation is: 500 hp gasoline engine using moderate boost with a 30% safety margin (500 x .625) x 1.30 = 406.25 lbs./hr. 406lbs/7.25 = 56 gallons/hour. If the pump that is being considered is rated in liters per hour, use the conversion factor of 3.785l/gallon. The pump described above would be rated at 56 gallons x 3.785 liters = 211.96 liters/hour.
near battery cables. Use clamps to secure AN hose every 15 inches, or 24 inches if a rigid tube is used. The following table will help you determine which hose size is correct for your application: These sizes are based on a nominal fuel pressure of 40 psi. Fuel Delivery Hose Sizes Gasoline Powered Engines Up to 499 HP .344” hose -6AN 500 - 799 HP .437” hose -8 AN 900 – 1100 HP .562” hose -10 AN Methanol Engines Up to 499 HP .437” hose -8 AN 500 - 799 HP .562” hose -10 AN 900 – 1100 HP .
amount of fuel that matches the maximum fuel pump output. The filter is always located after the fuel pump, however it does not matter if it is positioned in the front or rear of the vehicle (we prefer to put it toward the front for easy serviceability). AEM carries fuel filters for high-powered engines, which use an easy to find, high volume, replaceable element. It is imperative that a pre-filter be mounted to the fuel pick up in the tank.
Fuel Pressure Regulator and Pulse Dampener The fuel pressure regulator maintains a constant pressure across the fuel injector. The inlet manifold pressure varies with throttle angle, and engine speed. Small throttle angles and high engine speed produce low manifold pressure (high vacuum). While high throttle angles and low rpm give high manifold pressure. In addition to these conditions, low manifold pressure is associated with idle and high manifold pressure is at full throttle.
The two common types of fuel pressure regulators used are non-adjustable and adjustable. As the name implies, a non-adjustable regulator is set at a fixed value and is manifold-vacuum referenced (whenever a regulator is said to be vacuum referenced, this means that the inlet manifold vacuum/pressure is ported into the chamber above the regulator diaphragm).
An adjustable regulator allows the static pressure to be raised or lowered via an adjusting screw that acts on the diaphragm spring. On most adjustable regulators, when the screw is turned in pressure raises and when it is turned out pressure is reduced. Although we highly recommend installing a proper fuel delivery system, raising or lowering fuel pressure can compensate for fuel injectors that may not be properly sized for an application.
Basic Tuning Timing Pickup Confirmation The Timing Pattern Basics section above presented a brief overview of how the options and tables in AEM Tuner are used to configure a calibration for use with a certain timing pattern. This section will describe how to confirm the EMS is receiving the proper timing pattern information before attempting to start the engine for the first time.
The screen capture above shows a list of basic timing pattern channels. There are many others but this list will allow the tuner to confirm the basics. Verify proper main battery power and ground connections and turn the ignition switch to ON. Connect to the EMS with AEM Tuner and crank the engine with fuel injectors, ignition coils and fuel pump disabled. View or log the channels in the list above. Engine Speed – Calculated engine speed. Should not be zero during cranking. Confirm reasonable data.
Crank Count – Increments by one every time a crank tooth edge is detected by the ECU. Value will count from 0 – 255 and reset. This channel will remain zero unless there edge selection options turned on for the cam sensor input such as: Stat Sync’d – Turns ON when synchronization criteria are met. This channel should be off when the engine is not cranking. It should turn ON during cranking and depending on the timing pattern, it may take up to two engine revolutions.
Crank Tooth Period Missing Tooth Section Crank Count Cam Tooth Edge Detected The A Tooth channel counts from 0 to 57 then resets. The Fuel Tooth channel counts from 0 11 then resets (one loop through the tooth control table or 12 edges). A simple PC log like this recorded during cranking can be very helpful in troubleshooting timing pattern problems. Noise Electrical noise can cause the EMS to see more tooth edges than there are in reality.
common preventative measure for eliminating “noise” is to twist the wires together to minimize the electromagnetic field near the wires. On any EFI system, resistive spark plug leads are REQUIRED to suppress noise! Common resistive spark plug leads include those with a carbon impregnated fiberglass core or spiral wound filament around a carbon core wire. Another source of noise that can cause a misfire is an electrical “leak” in a plug wire or boot.
Ignition Timing Sync Wizard The PC must be connected to the EMS and the engine must be running. To minimize ignition timing fluctuation, the timing from the EMS can be locked at a given setting. Select or type in a value then click the Lock Ignition Timing at checkbox. Next measure the ignition timing at the balancer with a timing light and compare the actual reading to the commanded “locked” value.
Crank Fuel & Engine Start Typical Start Setup Tab Crank setup options Crank Advance – Desired ignition timing during cranking conditions Crank Inject All – When selected, all injector outputs will fire at the same time and inject fuel using the pulsewidth values defined in the Initial Crank Pulse table. Crank Min RPM – The minimum engine speed before fuel and spark events are allowed. Typically set to 50 RPM. Crank Max RPM – The maximum engine speed for cranking fuel and spark values.
2D Tables for Engine Start The Crank Injector Time table is the base commanded value for crank fuel. X-axis is throttle position. In the example above, the crank injector time is minimized at wide open throttle to serve as a flood clear mode. The Initial Crank Pulse table is a one shot pulse applied to all injectors when the EMS first detects a crank tooth edge. Page 149 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The Start Extra vs Temp and Start Extra Decay tables work together. Both are vs coolant temperature. An enrichment is applied from the Start Extra vs Temp and decays away according to the time defined in the Start Extra Decay table. Idle Air Control Idle air control (IAC) systems are used to stabilize idle speed during cold engine and after warm-up operations. The IAC system regulates the volume of air bypassed around a closed throttle butterfly valve.
Typical Idle Setup Tab Page 151 of 279 EMS-4 Install and Tuning Guide_Rev 1.
A/C On Delay, Units: Seconds - Description: The time between when the A/C request is switched ON and the A/C compressor is turned ON. Used to open the idle motor slightly before the increased load from the A/C compressor to counter-act idle surge. A/C Idle Load Comp, Units: Idle % Description: Amount of extra duty required to maintain the existing target RPM when the A/C compressor is enabled. The value can be positive or negative depending on how the idle air control motor responds.
100 Hz = 10,000 uS 300 Hz = 3333 uS Idle FB Max, Units: Idle %, Description: Maximum air bypass percentage allowed to maintain the target idle. A typical value is 15%. Before tuning the idle option, this value may need to be large in order to stabilize idle for normal tuning. After tuning idle, it is a good idea to narrow the feedback range to eliminate unwanted idle changes. Idle FB Min, Units: Idle %, Description: Minimum air bypass percentage allowed to maintain the target idle. A typical value is -5%.
2D Idle Control Tables The Idle Target Base table is used to set the desired engine idle speed vs coolant temperature. Typically, slightly higher target values are used at colder engine temperatures as shown in the example above. Page 154 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The Idle % vs Target table is used as the open loop set point vs target RPM. When entering into the idle control function, the ECU will command the output duty cycle to the value defined in this table. For example, using the table above if the current idle target is 1400 RPM, the ECU will command an IAC duty cycle of 40% then check to see if the actual engine speed is equal to the target RPM. If it is, no changes are made. If it is not, the ECU will adjust from this point.
The RPM Offset vs TPS table or “Throttle Follower” table is used to keep the idle control system from fighting the driver command during very light throttle applications like creeping in traffic. Sometimes very light throttle application by the driver will not make the TPS % exceed the value set for the Idle Off if TP Over option. When this happens the ECU will try to close the IAC valve to keep the idle speed at the target. This can cause a sluggish feel to the engine.
High Idle RPM Offset Units: RPM, Description: The additional amount of RPM added anytime the system goes into idle control. The RPM is added for the length of time specified in the Hi Idle Wait Time option. This function is also used anytime the car is below the High Idle Above VSS Value. Idle RPM Trim Start Units: RPM, Description: Additional RPM added when the engine starts. Uses the RPM Offset vs Start table to determine decay time.
3,000RPM. Start the engine. After a few seconds, confirm that the Idle Target parameter is 3,000RPM (if not zero-out all. Add or subtract idle percent from the Idle% vs Target Table until the Idle Learned Value parameter is 0% (you may notice that the idle motor will not rev the engine this high but that is common). Drop the Idle Target Base table to 2900RPM. Add or subtract idle percent from the Idle% vs Target Table until the Idle Learned Value parameter is 0%.
The X-axis of the fuel map is engine RPM. The Y-axis is engine load. The values within the table are injector pulsewidth in milliseconds where 1000 milliseconds = 1 second. Page 159 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Fuel Map Operating Areas WIDE OPEN THROTTLE ACCEL / LUGGING IDLE HEAVY LOAD PART THROTTLE CRUISE DECEL/OVER RUN Every engine is different but in general the main fuel and ignition maps can be broken up into areas of operation as shown above. Idle – Where an engine spends 99% of its time. Accel / Lugging – The area of the fuel map accessed briefly during snap accelerations. Also the area used during lugging conditions in high gear. Wide Open Throttle – Area accessed during wide open throttle operation.
The Warm Up Enrichment table is used to compensate for poor fuel atomization during cold start conditions. Note that “cold start” does not necessarily mean frigid arctic conditions. It applies to any condition when the engine is not up to normal operating temperature. Additional fuel is needed just after start and before the engine reaches normal temperature. Tuning Tip - When creating a new tune from scratch. Leave the warmup enrichment table zero’d out at first.
The Throttle Fuel Trim can be used to add a +/- fuel trim vs throttle position. Page 162 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The Air Temp Fuel Trim table is used to compensate for air density changes with inlet air temperature. It can also be used in a safety mode to add additional cooling fuel at very high inlet air temperatures on boosted applications. The Boost Fuel Trim table is used to add a fuel compensation vs engine manifold pressure. This table can be used in a number of ways.
100% more fuel needed here than at 100 kpa to compensate for the additional “atmosphere” worth of manifold pressure. A 100% trim will effectively double the fuel flow. The Main Fuel Map can then be configured to maintain the same target pulsewidth vs engine pressure. It will only vary vs engine RPM as shown below: Page 164 of 279 EMS-4 Install and Tuning Guide_Rev 1.
All values constant from 100 kpa up relative to pressure WOT throttle tuning can be accomplished very quickly using this method as you only have to worry about tuning vs engine RPM and not engine load. Complete your test run, dyno pull, etc. and review the AFR data. To make changes over a specific RPM range, highlight the range as shown and increase or decrease as necessary to enrichen or lean the fuel. Page 165 of 279 EMS-4 Install and Tuning Guide_Rev 1.
MODIFIED AREA START ABOVE 100 KPA Page 166 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The Gear Fuel Trim table can be used to trim fuel vs gear position. Note that the EMS must be configured to sense gear position for this table to function properly. There are two battery offset tables for fuel injectors. One is used for the primary injectors or base injectors if the system is not configured for staged injection. The other is used for the Page 167 of 279 EMS-4 Install and Tuning Guide_Rev 1.
secondary or staged injectors. These tables compensate for the variable opening time that results from changes in battery voltage. These tables must be developed with proper equipment and AEM has many injectors pre-configured for you in the setup wizard as shown below: If you can‟t find your particular injector in the list, contact AEM to have a flow test performed using your injectors. WARNING! EMS-4 SYSTEMS WILL NOT DRIVE LOW IMPEDANCE INJECTORS DIRECTLY.
FROM EMS-4 Page 169 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The Baro Fuel Trim table requires a barometric pressure sensor. Some plug & play EMS systems come equipped with a baro sensor. Check pinout sheet or schematic for more information. Alternatively, the baro sensor input can be defined as any available analog input using the selection dropdown as shown below: Page 170 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The User Fuel Trim table and function can be used to define any available analog input as a fuel trim. The User Fuel Analog In option is used to define the input. The table above defines a -50% to +50% trim based on that input. The X-axis in the table is 0 to 100% of the analog voltage input. This table is sometimes used with a 0 – 5V trim pot. The driver can manually adjust this trim any time. Page 171 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Individual cylinder trims are used to compensate for uneven air distribution. Each injector output has an associated trim table. The Injector 1 Trim table is used for the EMS injector #1 output. The X-axis of the table is engine RPM. Proper instrumentation is usually necessary to take full advantage of these tables. Either individual cylinder EGT data or individual cylinder AFR data is required.
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The Fuel vs Idle RPM table is used to trim the fuel injection pulse vs Idle Target Error. This table is not used very often. Page 174 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Fuel Trim Channels Fuel Map – The raw commanded pulsewidth value directly from the main fuel map Throttle Mod – The trim % taken from the Throttle Fuel Trim table Fuel Trim AIT – The trim % taken from the Air Temp Fuel Trim table Fuel Trim Baro – The trim % taken from the Baro Fuel Trim table Fuel Trim Boost – The trim % taken from the Boost Fuel Trim table Fuel Trim Coolant – The trim % taken from the Warm Up Enrichment table Fuel Trim Gear – The trim % taken from the Gear Fuel Trim table Fuel Trim Idle –
Fuel Trim 1 – The trim % taken from the Injector 1 Trim table (individual cylinder trims). Other cylinders work the same way. Fuel Inj 1 Pulse – The actual commanded pulsewidth for the injector #1 output after all trims have been applied. Additional Function Based Fuel Trims Nitrous Control – Option to turn the Nitrous control function on/off. Fuel trim will be applied according to the values in the N2O Fuel map. See section on the Nitrous Control function for more information.
of the throttle is consistent with the need for high-power AFR during acceleration, it is equivalent to the value needed for full power. The amount of enrichment required is largely dependent on the design of the inlet tract and placement of the injectors. Enrichment for systems where the injectors are placed far from the inlet valves will have to be higher than if the injectors are placed near the inlet valves.
Acceleration Fuel Function Options Accel TPS Sensitivty – The larger this number, the larger the calculated Accel dTPS value will be for a given change in throttle position. Determines how sensitive he accel fuel function is to changes in throttle position. Accel dTPS Trigger – The calculated Accel dTPS value must be higher than this number for the accel function to activate. Used as a filter to eliminate false triggering from normal signal noise. Accel Limit – Used as a clamp for the accel fuel function.
This table gives a % accel pump size, versus the dTPS value. This % size is relative to the current injector pulsewidth (PW). So if the current PW is 1,400 uS (1.4mS) and the % value was 75%, the base accel pump size would be 75% * 1.4mS = 1.05mS. Once a base accel pump size is generated, it is immediately multiplied by the Accel vs Throttle table. This is a TPS based table and serves to scale the output based on the throttle position when the accel pump was activated.
Next, it is multiplied by the Accel vs Engine RPM table, which is the RPM based correction for the dTPS component. This table usually starts at 100% and then decreases to a smaller value (sometimes 0%) at RPM values. This makes sense because the fuel delay is smaller at high port velocities; hence the accel pump can be smaller. Next it is multiplied by the Accel vs Coolant Temp table. This incorporates a coolant Page 180 of 279 EMS-4 Install and Tuning Guide_Rev 1.
based trim to accel fuel because a cold engine will need more accel fuel compensation than a warm engine. To recap what's happened, a filtered throttle position change has been detected and from this value, a base % accel pump was determined. Then it was corrected for TPS, RPM and Coolant temperature. Now, it is checked against the user option Accel Limit. If it is larger than this value, then it is reset to this value.
Accel dTPS – Displays the current delta TPS value Accel dTPS Latched – Displays the last activated delta TPS value Accel Trigger Count – Displays the current number of times the accel pump has been triggered. Resets at 255.
The spark plug gap on forced induction engines should be reduced REGARDLESS of the type of ignition system. We have read many instruction manuals for aftermarket ignition systems that recommend that the plug gap be opened up for better flame propagation. Although this recommendation may have had some merit when vehicles had carburetors, it does not apply to modern engines with electronic engine management systems.
has a lesser tendency to misfire under the extreme pressures of a racing engine combustion chamber. Also there are spark plugs made with exotic fine wire highly conductive center electrodes that require less energy to fire such as the Denso Iridium that are well suited to racing conditions. The following is a chart of gap sizes for various engines on gasoline: Naturally Aspirated up to 11.0:1 CR 1.1mm (.044”) Naturally Aspirated 11.0:1 to 14.0: 1.8mm (.032”) Forced Induction to 20-PSI .7mm (.
the hot unburned portion of the fuel mixture (typically referred to as end gas) in the combustion chamber. The remaining charge portion is compressed first by the upward piston movement and then by the moving flame front. Knocking is the almost instantaneous ignition of part of the remaining mixture. This mixture auto ignites because the rapidly rising pressure and temperature caused by the piston movement and the expanding gas from the flame front are sufficient to ignite the remaining gasses.
Too lean of an air/fuel mixture. The following tuning adjustments can be performed on an engine to reduce or eliminate knocking: Reduce ignition timing. Verify that the air/fuel mixture is adequate for your engine set up. Verify that the spark plugs are of proper heat range. Preignition is the ignition of the charge in the combustion chamber before the spark occurs. This type of ignition is caused by a very hot, or even incandescent surface in the combustion chamber.
very small shiny beads on the porcelain of the plug, there is a good chance that the engine is knocking. Retard the timing to eliminate the knocking, enrich the mixture, or use a higher octane of fuel. The combustion chamber plays an important role in the amount of ignition timing that can be used for the various operational phases of an engine. The most common type of combustion chamber design used in contemporary engines is a four-valve/cylinder, pent roof chamber.
Squish is accomplished via a small gap between the head deck and the piston top. The decrease of this gap drives the inlet charge toward the spark plug electrode. An additional benefit of having this small gap is the reduction of end gas volume at the extreme edges of the cylinder. This reduces the tendency for spark knock and leads to a reduction of Hc emissions.
Naturally Aspirated Piston Engines W/ Pent roof Combustion Chamber Ignition Timing L 100 15 22 32 33 33 33 33 33 O 90 15 22 33 34 34 34 34 34 A 80 15 22 33 35 35 35 35 35 D 70 15 23 35 35 35 35 36 36 60 15 24 35 35 36 36 37 37 I 50 15 24 35 35 36 36 37 37 N 40 15 24 37 37 38 39 40 40 30 15 24 37 37 38 39 40 40 K 20 15 25 40 45 45 45 45 45 P 10 15 25 40 45 45 45 45 45 1000 2000 3000 4000 5000 6000 7000 80
Turbocharged Piston Engines W/ Pent roof Combustion Chamber Ignition Timing L 300 11 14 23 23 24 24 24 24 O 275 11 15 24 24 25 25 25 25 A 250 11 15 24 24 26 26 26 26 D 225 11 16 24 26 27 27 27 27 200 12 17 26 27 27 27 27 27 175 12 19 28 29 29 29 29 29 I 150 12 20 29 30 30 30 30 30 N 125 12 20 30 30 31 31 31 31 100 15 22 32 33 33 33 33 33 K 75 15 23 35 35 35 35 36 36 P 50 15 24 35 35 36 36 37 37 A 25
Naturally Aspirated Piston Engines W/Wedge Combustion Chamber Ignition Timing L 100 15 22 32 35 35 35 35 35 O 90 15 22 33 35 35 35 35 35 A 80 15 22 34 35 35 35 35 35 D 70 15 23 34 35 36 36 37 37 60 15 24 35 35 36 36 37 37 I 50 15 24 35 35 36 36 37 37 N 40 15 24 37 37 38 39 40 40 30 15 24 37 39 39 39 40 40 K 20 15 25 40 47 47 47 47 47 P 10 15 25 40 47 47 47 47 47 1000 2000 3000 4000 5000 6000 7000 8000 A
Turbocharged Piston Engines W/Wedge Combustion Chamber Ignition Timing L 300 11 14 23 23 24 24 24 24 O 275 11 15 24 24 25 25 25 25 A 250 11 15 24 24 26 26 26 26 D 225 11 16 24 26 27 27 27 27 200 12 17 26 27 27 27 27 27 175 12 19 29 30 30 30 30 30 I 150 12 20 30 31 31 31 31 31 N 125 12 20 32 32 33 33 33 33 100 15 22 34 35 35 35 35 35 K 75 15 23 34 35 36 36 37 37 P 50 15 25 40 47 47 47 47 47 A 25 15 2
Ignition Map The Ignition Map is the main ignition table in the calibration. Ignition Trims Similar to fuel there are several 2D tables that can be used for trimming ignition timing. The following section describes each. Page 193 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The Air Temp Ign Trim table is used to trim the ignition timing vs inlet air temperature. Often used on boosted applications as a safety mode. Ignition timing is reduced at very high air temperature readings to avoid detonation. Note that the trim values in this table are added (positive values) or subtracted (negative values) from the base ignition timing. The Coolant Ign Trim table is used to trim the ignition timing vs coolant temperature.
degrees of additional timing during warmup can help quite a bit. Note that the trim values in this table are added (positive values) or subtracted (negative values) from the base ignition timing. Individual cylinder trims are used to compensate for uneven air/ fuel distribution or cylinder cooling problems. Each EMS coil output has an associated trim table. The Coil #1 Ign Trim table is used for the EMS Coil #1 output. The X-axis of the table is engine RPM.
The Ign vs Idle RPM table is used to trim ignition timing vs Idle Target Error. Ignition Trim Channels Ign Map - Displays the current ignition timing from the Ignition Map Ign Trim AIT - Displays the current ignition timing correction for air temperature from the Air Temp Ign Trim table Page 196 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Ign Trim Coolant - Displays the current ignition timing correction for coolant temperature from the Coolant Ign Trim table Ign Trim Idle - Displays the current ignition timing correction for idle from the Ign vs Idle RPM table Ign Trim Gear - Displays the current ignition timing correction for idle from the Gear Ign Trim table Ign Trim 1 - Displays the current ignition trim (in degrees) from the Coil 1 Ign Trim table. All other coil output are similar in function.
the option VSS Cal * 8 to ON. This will allow more range. VSS Filter Units: On/Off Description, Used to smooth the speed sensor. Use as first defense. VSS Hall Falling Units: On/Off Description, Sets falling edge as significant edge. VSS Hall Rising Units: On/Off Description, Sets rising edge as significant edge. VSS Smooth Units: On/Off Description: Used to smooth the speed sensor. This is very aggressive. This should be used after VSS Filter but only if needed.
EMS-4 GPIOs GPIO as PWM driver output example The example above illustrates a GPIO as a PWM duty cycle output such as an idle air control solenoid or boost control solenoid. The power input to the solenoid must not be connected directly to the battery or any full time voltage source. The power should come from a switched fused supply. See the EMS-4 System Diagram for more information. Page 199 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Idle PW Output – Option assigning pin GPIO5 to the Idle Control output function Idle PW Frequency – The period in microseconds assigned to this output pin. 1 microsecond = 0.000001 seconds or 1 x 10-6 seconds 33000 x 1 x 10-6 seconds = 0.033 seconds Frequency = 1 / Period so: 1/0.033 = 30.3 Hz These setting would configure the EMS to output a 30 Hz duty cycle switched ground output on pin GPIO5. GPIO5 40/64Mhz – Scaling option sometimes used to allow much higher frequency output signals. Default is OFF.
GPIO as Switched Input example The example above illustrates a GPIO as a switch input for use in activating certain EMS functions. Page 201 of 279 EMS-4 Install and Tuning Guide_Rev 1.
In the example above, GPIO5 is defined as the internal logging activation switch input. The Gnd=On criteria is set meaning the switch input will be considered on when the switch completes continuity to ground as shown in the diagram above. The analog status of all GPIO pins can be monitored by viewing/logging the GPIOX AN channel as shown below: Logging Off Switch High Logging On Switch Low (GND) Page 202 of 279 EMS-4 Install and Tuning Guide_Rev 1.
GPIO as simple switched output driver example In the example above, GPIO5 is setup as a simple switched output driver to activate a fuel pump relay. Page 203 of 279 EMS-4 Install and Tuning Guide_Rev 1.
As shown above, GPIO5 is set up as a fuel pump function output. It will follow all rules associated with a fuel pump function: 1. At power up, the output will activate and stay on for the length of time defined for Fuel Pump Prime above. 2. If no crank tooth pulses are detected, the output will turn off. 3. If crank tooth pulses are detected (engine spinning), the output will turn on to activate the fuel pump. Page 204 of 279 EMS-4 Install and Tuning Guide_Rev 1.
GPIO as simple 0-5V analog input example GPIO as Analog Input combined with Other Functions Tuning Tip The following is a creative example of how the GPIOs can be combined and used with other software functions to accomplish complex objectives.
System Schematic Switch 7 Setup Options Page 206 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Switch 7 is a user created switch analog input channel. Once all conditions have been met, it activates an internal channel that is broadcast in the EMS and can be used as activation trigger for any logic that can take a manual/electrical switch input as an activating condition. Switch 7 Analog In – The input pin assigned to the Switch 7 Function Switch 7 On Above - Voltage threshold above which the switch 7 function is ON. Switch 7 On Below – Voltage threshold below which the switch 7 function is ON.
The Alt Function is another unique feature of the EMS. It‟s most often used in conjunction with the 2 step rev limiter to create a turbocharger anti-lag function. A turbocharged drag race vehicle can use this function to build boost on the starting line. The Alt function when activated can retard the ignition timing and add fuel effectively turning the turbine housing into a fuel afterburner. This adds tremendous energy to the turbocharger and increases turbine speed, building boost.
Data logging All EMS systems feature two methods for data logging. One is called “PC Logging” where the AEM Tuner software records data displayed on-screen directly to the PC memory. The other is called “Internal Logging” and uses on-board logging memory within the ECU to store data. The data logging setup is saved as part of the calibration file and must be configured properly to work.
To begin a PC log, AEM Tuner must be connected to the ECU. Select Start PC Logging from the menu item above or hit the F6 key. Select Stop and Save from either the menu items above or the status bar logging item. The dialog above will be displayed prompting the user to assign a file name to the log or accept the default log file name.
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The Open after save selection prompts AEM Tuner to automatically launch AEM Log software after the file save. For more information on using the included data analysis package, AEM Log, see the included AEM Log User‟s Guide in the Instructions folder in the AEM Tuner directory. Internal Logging All Series 2 EMS controllers with the exception of the EMS-4 include 1Mb of internal logging memory. The EMS-4 features 8Mb of internal memory space. Page 212 of 279 EMS-4 Install and Tuning Guide_Rev 1.
ECU Internal Logging Setup – Opens a dialog window that allows the user to configure the internal logging settings of the EMS. EMS Internal Logging Setup Dialog Logging Conditions Logging Conditions – Defines the activation criteria for the internal logging function. Logging is Off – Internal logging function is disabled. Page 213 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Logging is on when engine is running – When engine speed is greater than 0, data will be logged. Logging is on when the vehicle is moving – When the vehicle speed is greater than 0, data will be logged. Note that this setting requires a properly configured vehicle speed sensor. Logging is on at full throttle – Data will be logged at wide open throttle only.
Internal Logging Memory Control Select Loop Logging to continue logging after all memory is used. Only the oldest data will be lost when the log loops. Use the slider to select the logging rate. The rate, channels selected and EMS logging memory capacity will be used to estimate the log run time. Download EMS Log Menu Item Download EMS Log – Select this item when connected to the EMS to download the current logged data file.
Advanced Tuning Boost Control The AEM EMS has a very comprehensive and flexible boost control function. Using a pulse width actuated solenoid, boost can be controlled by vehicle speed, throttle position against rpm, and a switch input for low and high settings. The first step in creating a new setup is determining what frequency the solenoid needs to be operated. This information is typically provided by the manufacturer of the part.
1/0.033 = 30.3 Hz These setting would configure the EMS to output a 30 Hz duty cycle switched ground output on pin GPIO7. The Boost WG Base Duty table example above contains a 50% duty cycle setting everywhere. This table combined with the options above will result in the following output waveform on the GPIO7 pin after a power cycle: Page 217 of 279 EMS-4 Install and Tuning Guide_Rev 1.
This is a 30Hz, 50% duty cycle signal. The solenoid will be ON when the signal is low and OFF when the signal is high. Inverting the output The PWM output can be inverted to allow more flexibility in the plumbing configuration. The Boost WG 1 Invert option will control the output configuration. The example below is setup with a flat 20% duty cycle in the Base Duty table: The setup above will result in the following output signal pattern: Page 218 of 279 EMS-4 Install and Tuning Guide_Rev 1.
If the Boost WG Invert option is set to ON as shown above, the 20% duty cycle command will now result in the following output waveform: Page 219 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The specific wastegate type that will be used will also need to be determined when installing the boost solenoid. Illustrated below are typical ways of routing the boost (vacuum) lines with three different wastegate types. Page 220 of 279 EMS-4 Install and Tuning Guide_Rev 1.
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User Definable Options for Boost Control Boost WG Duty Max Units: % Duty Cycle Description: Wastegate feedback maximum range. This sets the maximum allowable duty output to the boost control solenoid, preventing overdrive of the solenoid. Allows a narrow range of operation for precise boost control. Because certain solenoids will not function efficiently at specific duty cycles, manufacturers require limitations to be set. Boost WG Duty Min Units: % Duty Cycle Description: Wastegate feedback minimum range.
Description: Sets the maximum feedback correction allowed in the positive duty direction when using P+I control only. Used to set correction limits and help stabilize boost. This function can help prevent overshooting. Boost FB -Limit Units: % Duty Cycle Description: Sets the maximum feedback correction allowed in the negative duty direction when using P+I control only. Used to set correction limits and help stabilize boost. This function can help prevent overshooting.
Units: On/Off Description: Inverts the output signal. This option is based on tuner preference. Generally used when the wastgate type or solenoid is wired in such a way that low duty cycles equate to high boost and high duty cycles equate to low boost. When ON, this algorithm will be opposite. Boost WG Output 1 Description: Defines the output pin to be used for the boost control function. Fuel Cut Load Units: Engine Load Description: Boost fuel cut that when over the engine load specified, 100% fuel is cut.
Repeat for other duty cycles, for instance 15%, 20%, 25%, 30%, etc… until you have reached all possible boost levels you wish to run. Save datalogs of relevant data (Boost WG 1 output, Engine Load, Throttle, Gear, Engine Speed) and/or write down the maximum boost level achieved using each duty cycle (see example below).
3. Using the data gathered in step 2, enter the duty cycle info into the Boost Target Comp table. This table allows the EMS to use the correct duty cycle for various Boost Target levels. Set the entire WG Base Duty map to zero. In the example below, the EMS will use 55% duty cycle to when the desired Boost Target is 230kPa. 4. Next, configure the Boost Target tables. There are four tables that can be used, and the values from all tables are added together at all times.
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5. Here is an example of a more complex Boost Target setup. Let us assume the vehicle‟s aero package generates significant downforce and this provides more traction at high speed. The example below will add 10kPa to the Boost Target at 80 MPH, and 20kPa to the boost target above 100MPH. This would result in a boost target of 210kPa in 5th gear at 80 MPH and 220kPa in 5th gear at 112MPH. 6. All 4 tables can be used in conjunction if the tuner desires.
7. Note that when using PSI for Load units, (-14.7) psi is the lowest possible value. Setting any table to 0psi (which is not the lowest possible value in the table) will cause that table to increase the Boost Target by 14.7 psi! The example below uses the exact same Boost Target settings but all tables are displayed in PSIg units rather than kPa. Page 229 of 279 EMS-4 Install and Tuning Guide_Rev 1.
8. The Boost Error Duty table can be used for closed-loop boost feedback. If the measured Engine Load is below the desired Boost Target, the Boost Error Duty table can increase the duty cycle of the boost solenoid to reach the desired Boost Target. It is recommended to leave this table set to zero (or very small changes such as +/-1) when configuring other boost control settings. Page 230 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Knock Control The Knock Sensor Cal table defines an RPM dependent threshold to filter out background noise. Setting up this table is key to the success of knock control. Whenever the knock sensor voltage output exceeds this table's value at the specified engine speed, it is considered to be "real knock". The difference between the actual knock signal and this threshold value determines the severity of the knock.
Add Fuel due to Knock The Knock %Rich/Volt will add a percentage of fuel per volt above the specified threshold. The maximum that the EMS can add is set by Knock Fuel Add Max. The EMS will return the fuel back to normal based on Knock Decrease Fuel and the Knock Restore Rate. Remove Timing due to Knock The Knock Retard/Volt value will remove your specified amount of timing per volt above the threshold. The maximum value that the EMS can remove from the engine will be set by the Knock Ign Rtd Max.
Traction Control Most OEM and available aftermarket traction control systems use the differential of a front and rear wheel speed sensor to determine traction conditions. While this is great way to control wheel slippage, it does not address all wheel drive (AWD) vehicles as all wheels spin at the same rate. AWD manufacturers do not use traction control on their vehicles as power distributing to four wheels is typically sufficient.
B. Option TC Timebase ON: 1. Option TC Speed/Time ON: 2. Option TC Speed/Time OFF: The parameter Engine Accel raw can be used to view or log the results from the calculation above. Once the Raw Engine Acceleration is calculated, a sensitivity factor is applied and the result is scaled versus the option TC Max. The calculation is as follows: where TC Max is the maximum raw engine acceleration rate possible under optimum traction conditions.
The log files below show the results. The top plot is a log of the channels Engine RPM and Engine Accel Rate and was recorded using the TC Sensitivity RPM Table above. Page 235 of 279 EMS-4 Install and Tuning Guide_Rev 1.
The next log shows the effect of increased sensitivity at low RPM. It was recorded using the following Sensitivity Table: Note the increased sensitivity at low RPM in the second plot. If the TC vs Road Speed option is checked, the sensitivity will be based on vehicle speed. If this option is not checked, the sensitivity is based on engine RPM. Page 236 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Trip Tables With traction control enabled, the parameter Engine Accel Rate is compared to limits identified in the following tables: TC Ignition Retard Trip Table TC Ignition Cut Trip Table TC Fuel Cut Trip Table The above tables are gear position sensitive and allow the user to define an Engine Acceleration Rate limit versus gear position. The above trip table for the ignition retard function shows an increasing limit with gear position.
The trip tables for the ignition cut and fuel cut functions are set up in a similar fashion. Normally, the first line of defense for a loss of traction condition is ignition retard. If the ignition retard function is unsuccessful, an ignition/fuel cut combination can be implemented. . User Definable Traction Control Options Traction Control Units: On/OffDescription: Enables traction control.
TC Fuel Restore Units: %Description: This option defines the amount of fuel cut % removed per engine revolution. A small number will remove the cut slowly. A large number will remove the cut quickly. TC Gear From Selecto Units: On/Off Description: Use this option for automatic transmission applications where a variable resistance potentiometer is used to determine gear lever position.
Traction Control Tuning Procedure 1. If the vehicle has a manual transmission with no gear position sensor, use the Configure Gear Ratio Wizard to setup the gear ratio table. If the vehicle has an automatic transmission with a gear position sensor, select the option TC Gear from Sensor. 2. AEM recommends starting with the following options settings for calculating Raw Engine Acceleration: TC Speed/Time = ONTC Timebase = OFF 3.
The above log shows Engine Speed, Engine Accel Rate, and Ign Timing. For this example, the low RPM sensitivity was set very high to illustrate the function. The ignition retard function can be clearly seen as well as the restore function. Page 241 of 279 EMS-4 Install and Tuning Guide_Rev 1.
2Step Rev Limiter Secondary rev limiters (2 step) are most commonly used in drag racing for consistent vehicle launches. However, secondary rev limiters can also be used for full throttle shifting, anti-lag, valet parking, etc. There are many different ways to install and program a 2Step Rev Limiter with the AEM EMS. Although any switch can be used, utilizing the factory clutch switch is most common. Most vehicles use a pull to ground switch.
Options for the 2Step Rev Limiter 2Step Fuel Cut Units: RPM Description: User defined RPM to enter the secondary fuel cut rev limiter. Naturallyaspirated engines will use this for soft launches whereas turbocharged vehicles may not cut fuel to encourage anti-lag spool up. 2Step Ignition Cut Units: RPM Description: User defined RPM to enter the secondary ignition cut rev limiter. 2Step Max VSS Units: Vehicle Speed Description: Vehicle speed threshold to deactivate the 2step rev limiter.
exceeded, 100% cut duty is applied. Automatically set by rev limiter setup wizard. 2Step Retard C Units: Constant Description: Offset used for ignition timing retard calculation while 2Step conditionsare met. Cut Duty = Cut C + ((Desired RPM Control Range/50)) * Cut M. The higher the value for Cut C, the more ignition retard is applied once the RPM target isreached. Once Desired Control Range is exceeded, maximum ignition retard is applied. Maximum timing retard depends on ignition range.
O2 Feedback To control the engine's fuel delivery system, the EMS can be programmed to run open loop and/or closed loop O2 feedback. Closed loop uses feedback from the oxygen sensor to make temporary, but immediate, corrections to the injection to maintain a target AFR. The type of an O2 sensor will determine how O2 feedback can be controlled. Due to the nature of standard narrow band O2 sensors, 14.7:1 is the only air fuel ratio that can be accurately maintained in closed loop.
loads because of the sensor's inaccuracy outside the stoichiometric rangeand at high exhaust gas temperatures. However, O2 feedback can be used at high engine loads with a quality UEGO sensor. O2 FB Rate Units: mS Description: O2 feedback base timer for both proportional and integral terms. This is how often the air fuel ratio is referenced to determine the necessary correction. A smaller number gives a faster response by effectively increasing the gain.
O2 FB Over Clear Units: On/Off Description: Sets O2 feedback to zero when ouside the load, coolant, or engine speed thresholds. After these parameters are met, the next condition will typically be different from before. This function is used to allow the O2 feedback to clear its memory and start from zero again. 2-D Tables for O2 Feedback O2 FB Time vs Temp Table Units: Time After Start Time vs.
O2 FB Int Gain table Units: Integral Gain vs. RPM Description: Integral control is implemented through the introduction of an integrator.This is used to fine tune the O2 feedback at the O2 Target once the proportional has acted in getting close to the target. Note: start tuning the O2 feedback with thisoption at zero, until the proportional has the feedback close to the target, then step this in slowly until the feedback holds the O2 Target.
3-D Tables for O2 Feedback O2 FB O2 FB Target Units: Engine Load vs. RPM vs. AFR Description: O2 feedback target for specific engine loads and RPM. This map is used Page 249 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Channels (can be viewed or logged) O2 FB Delay Units: Seconds Description: Time delay for O2 feedback operation after engine start. O2 Target Units: AFR Description: Air fuel ratio that directly corresponds with the AFR Map. O2 #1 Units: AFR Description: Scaled air fuel ratio from Lambda #1. O2 #1 Target Error Units: AFR Description: Difference between the actual air fuel ratio and the targeted air fuel ratio from Lambda #1.
code. Accel O2 FB Hold Units: mS Description: The current hold time for the O2 feedback to be reinstated after the accel/decel function has been triggered. Page 251 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Nitrous Control There are several ways to control nitrous oxide with the AEM EMS. The user has complete control over all of the nitrous functions, when it activates and deactivates the solenoids, and how much fuel and timing trims are added. Below is a diagram ofhow AEM recommends wiring a nitrous setup. User Definable Options for Nitrous Nitrous Control Units: On/Off Desciption: This option enables the nitrous control. Set this to ON to allow the nitrous control to become active.
N2O Off Above Load Units: Engine Load Desciption: Above this engine load the EMS will deactivate the nitrous control. This can be used to spool a turbocharger, which will turn OFF the nitrous once the desired boost has been reached, or as a safety measure to prevent the nitrous from being active in an overboost situation. When the engine reaches this load point, theEMS will cut the active signal to the nitrous relay, and disable any trims that have been set.
3-D Maps for Nitrous N2O Fuel map Units: Engine Load vs Engine Speed vs Fuel % Description: This map allows a percentage of additional fuel to be added or subtracted from the base map when the nitrous options become active. This map allows adjustment over engine speed and engine load. N2O Ignition map Units: Engine Load vs Engine Speed vs Degrees Description: This map allows ignition timing to be advanced or retarded against the base ignition map when the nitrous control is active.
Channels (can be viewed or logged) Nitrous Units: On/Off Description: Displays the current status of the nitrous function. N2O Fuel Units: Fuel %Description: Displays the current amount of fuel added or subtracted from the N2O Fuel map. N2O Spark Units: Degrees Description: Displays the current amount of ignition timing advanced or retarded from the N2O Ignition map. Note: All of the nitrous options must be met for the EMS to activate the selected output and add the fuel and ignition trims.
Anti-Lag Turbo lag is defined as the time delay before the turbocharger has produced boost pressure. Since turbochargers are designed and sized to operate at specific rpm ranges and air flow conditions, some turbo lag is inherent in the system. To fully understand turbo lag, you must first understand the operation principles behind what causes a turbo to make boost. Boost is not made by rpm alone.
User Definable Options for Drag Race Anti-Lag Alt Ignition Fixed Units: On/Off Description: Enables the Alt Spark Fixed option in order to maintain a constant ignition timing value for anti-lag. Alt Spark Fixed Units: Degrees Description: Sets a fixed ignition timing value while the alternate conditions are met.This is enabled by the Alt Ignition Fixed option. Alt Spark Trim Units: Degrees Description: Amount of ignition spark to be trimmed (+/-) when the alternate trims are active.
Alt Function Output Units: User Defined Output Description: If the Alternate function is activated, this output channel will be activated also. Can be used to drive an LED, injector, etc. Alt Function Input Units: User Defined InputDescription: Input switch that triggers the alternate function. Channels (can be viewed or logged) ALT Units: On/Off Description: Displays the current status of the alternate function.
Analog Input Switch The AEM EMS can turn a 0-5V input into a switched input. This allows you to configure any analog channel with a switching point to activate. The is commonly used with shift retard with a 0-5V strain gauge. However, the analog input switch can be used for many other purposes. The analog input (Switch #7) works by setting a high and low voltage range with a throttle and engine speed threshold.
Staged Injection The AEM EMS has up to 10 individually controlled injector drivers (depending on the system). EMS-4 systems have 4 injector drivers. By default, they are assumed to be driving primary fuel injectors. Alternately, they can be defined as secondary, or "staged" injectors. These can be activated on an as-needed basis or by a user defined ratio between the two based on engine speed and load. The staged injectors are fully sequential with user defined, independent phasing.
3-D Maps for Staged Injection Fuel Difference map Units: Fuel vs RPM vs Load Description: Allows a programmable fuel percentage when using the Diff Switch Input option. Channels (can be viewed or logged) Fuel Diff Units: %Description: Displays the current % of fuel (from the Fuel Difference map) that is being directed to the staged injectors.
Fuel Inj Duty Sec Units: % Description: Displays the current injector duty cycle of the staged injectors. Fuel Inj Pulse Max Units: uS Description: Displays the maximum available injector time for the current enginespeed. Fuel Inj Pulse Pri Units: uS Description: Displays the current pulsewidth of the primary injectors minus the Battery Offset Primary Table. Fuel Inj Pulse Sec Units: uS Description: Displays the current pulsewidth of the staged injectors minus the Battery Offset Staged Table.
Tuning Staged Injection First, confirm that all of your primary injectors are defined properly. They must be "active" as well as defined as either Primary or Secondary. To do this, go to the Coils/Inj tab: In the example above Injectors #1 and #2 are defined as Primary and Injectors #3 and #4 are defined as Secondary. You need to define where, in the engine cycle, you want the staged injectors to begin their injection pulse.
setup wizard that will help define these flow difference options: The example above defines 2 Primary injectors at 440cc/min each and 2 Secondary Injectors at 750cc/min each. The last thing required to define the injectors is to tell the EMS how fast the injector responds to the fuel pulse signal. Under Trims tab is the Battery Offset Staged table. This is how long the secondary injectors take to start flowing fuel after they have been turned ON and is a function of battery voltage.
injectors. This sets the injectors to run only on the primary injectors until the base injector duty cycle exceeds the Injector Duty Max option. Once that has occurred, the fuel in excess of Injector Duty Max is routed to the staged injectors. The time set in the Injector Min option keeps the system from quickly switching back and forth between the two if the duty were to stay right at the Injector Duty Max threshold.
Fuel Trim Bat-Pri and Fuel Trim Bat-Sec channels. To determine how the Fuel Difference Map is being used, monitor the Fuel Difference, Fuel Diff Trim and Fuel Diff channels. Switched Ignition Retard/Cut Switch Retard Output Pr: This option allows the output pin to be activated for a controlled amount of time prior to the timing retard/cut happening. This allows the system to prime the pneumatic actuator before decreasing engine power.
Time during which the ignition remains at the max retard. Can be adjusted for each gear. (Recommended values: 80-150ms) Switch Rtd Adv Time: Time during which the ignition is increased or „ramped back in‟ as opposed to immediately changing back to original ignition table values. Switch Rtd ReArm: Wait time between shift events. Intended to prevent extra shift events if the switch is pressed too early or held for too long.
See diagram above. Controls the on-time of the control output. Switch Rtd Step: Defines the ignition timing step sizes applied as the timing is ramped out. Page 268 of 279 EMS-4 Install and Tuning Guide_Rev 1.
Glossary of Terms 4 Stroke Cycle Intake - During the intake stroke, the piston is moving from top to bottom and the intake valve is open. As the piston moves down, a vacuum is created which draws the air/fuel mixture into the combustion chamber. The intake valve is closed after the piston reaches the bottom. This position is normally called bottom dead center (BDC) Compression - During the compression stroke, the piston moves up and compresses the air/fuel mixture against the cylinder head.
BDC Bottom dead center; the extreme lowest position of the piston during its stroke. Boost Describes positive pressure in the intake manifold relative to atmospheric pressure. Standard atmospheric pressure is 14.5 psia. 10 psi of boost would result in 24.5 psia in the manifold. Breakpoints Define the axis values on two dimensional or three dimensional lookup tables BSFC Brake Specific Fuel Consumption or BSFC is the fuel flow rate per unit power output.
Combustion The burning of the fuel-air mixture in the cylinder. Combustion Chamber Space left between the cylinder head and the top of the piston at TDC; where combustion of the air-fuel mixture takes place. Compression Ratio The ratio of the cylinder volume at BDC to the volume at TDC. Options Single value in an engine calibration. Can sometimes be referred to as an option. Options and tables (2D and 3D) make up the tuneable portion of an engine calibration file.
Drivability Condition describing a car in which it starts easily and idles, accelerates and shifts smoothly and with adequate power for varying temperatures. Driver In automotive electronics, refers usually to a transistor circuit that is designed to either source or sink electrical current. Duty Cycle In components which cycle on and off at a given frequency, the measurement of the amount of time the component is on versus the time it is off.
Type of sensor used in all Pro Flo distributors for measuring crankshaft position. Outputs a square wave signal pattern that is either low (ground) or high (reference voltage) depending on whether or not a tooth is passing near the sensor. Hg The chemical representation for the element Mercury. High Impedance Refers to injectors that have coil resistance values of 12.0 ohms or more Hot Keys Single or combinations of key strokes that can be programmed to perform certain tasks.
Math Channel In data analysis software, a channel calculated using raw data and mathematical functions. Can be included in a plot with other data. mS Abbreviation for millisecond or one thousandth, 0.001 seconds. Open Loop Fuel Control Method of controlling fuel flow without modification from a feedback variable such as oxygen content. Outing In data analysis software, refers to a complete set of data. Parallel Circuit Contains two or more circuit elements that have the same voltage measured across each.
psia Abbreviation for pounds per square inch absolute. A unit of pressure measurement relative to a perfect vacuum. RS232 A common standard used in serial communication between a PC and an engine controller. RXD Abbreviation for Receive Data. Saturated Driver A power transistor driver that turns fully on for the entire duration of the injector PW.
the air. For gasoline, this ratio is 14.7:1 or 14.7 parts of air to 1 part fuel. Switch A device that can break an electrical connection interrupting the current or diverting it from one conductor to another. Switched Ground Using an electromechanical of electronic switch to connect a circuit element to a ground reference. Switched Power Battery power provided to the system when the ignition switch is in both the "run" and "start" positions.
in the manifold. Volumetric Efficiency The intake system on a spark ignited engine, restricts the amount of air that an engine of a given displacement can flow. The parameter used to measure the effectiveness of an engine's induction process is the volumetric efficiency. It is defined as the volume flow rate of air into the intake system divided by the rate at which volume is displaced by the piston.
Index 2Step Rev Limiter, 5, 240, 241 30-6905 kit, 10 Air Temp Sensor, 27 Analog Input Switch, 5, 257 Anti-Lag, 5, 254, 255 autoignition, 184 backshell, 10, 12 Boost Control, 5, 214, 220, 222 Calibration Compare Tool, 59 Calibration File, 40 Cam Count, 103, 141 Cam Sensor, 33, 34 CAN enabled devices, 19 CDI, 25 Change Injector/Pressure Wizard, 72, 73 Channels, 40 coil driver, 22, 23, 25 compression ratio, 141, 185 Configure Gear Ratio Wizard, 73, 74, 238 Configure Output Dialog, 57 Configure Telemetry Dialog
Software Installation, 37, 38, 39 Spark Plugs, 179 Spark Teeth, 103 Spark Tuning General Concepts, 4, 100 Squish, 185 Staged Injection, 5, 74, 258, 259, 261 Staged Injection Wizard, 74 Stat Sync’d, 142 Switch 7, 202, 203, 204, 206, 257 Sync Errors, 142 Tables, 40, 45 Tabs, 40, 48, 49 Timing Errors, 142, 143 Page 279 of 279 Timing Pattern Basics, 4, 101, 104, 140, 142 Timing Pickup Confirmation, 4, 140 TPS sensor, 71, 128 Traction Control, 5, 173, 231, 236, 238 Transistors, 109 Upload Calibration, 50, 51 U
