Installation Manual

INSTALLATION INSTRUCTIONS 3
M S D • W W W . M S D P E R F O R M A N C E . C O M • ( 9 1 5 ) 8 5 7 - 5 2 0 0 • F A X ( 9 1 5 ) 8 5 7 - 3 3 4 4
As you can see from the chart, most factors will change throughout the range of the engine operation.
The Digital E-Curve allows you to make timing changes based on these factors.
Example: An engine has 11:1 compression, a high energy ignition and turns 5,500 rpm. With the
specifications given, you will have to retard the timing for the high compression and high energy
ignition. By comparing the engine’s specifications against the chart, a usable timing guideline can
be found. Engines with a combination of items from both columns will require a timing that is set in
the mid range.
Obviously a full technical explanation of correct ignition timing would be very complicated. The best
way to arrive at a suitable ignition curve for your engine is to use the Ignition Timing Factors Chart
as a guide and compare it to the Advance Graphs in Figure 3 until a suitable curve is found. When
selecting your advance curve, use detonation (engine ping) as an indicator of too much advance, and
a decrease in power as an indicator of too little advance. Also consider how the engine cranks and
starts. Too much advance can cause an engine to crank slow or even kick back. Here are a couple
of suggestions.
• Use as much initial advance as possible without encountering excessive starter load.
• Start the electrical advance just above the idle rpm.
• Select an advance curve that produces good acceleration without detonation.
SETTING UP THE DISTRIBUTOR
Rotate the engine to TDC then to 12° - 15° BTDC. With the rotary switches set to "1" and "7" (These
settings will be used to start the engine and adjusted later.) install the distributor with th rotor pointing
to the number 1 spark plug wire and start the engine.
With the engine running and a timing light connected, adjust the timing to the desired Total Timing.
(Example 32° without vacuum advance) Once you've set the total timing, turn the engine off and
remove the distributor cap. Set the rotary dials to achieve the desired timing curve (Figure 3 and 4).
For example with total timing set at 32° and the rotary dials set to "2" and "9". The engine will idle
at 12°, timing will start to advance at 1,100 rpm and will be fully advanced by 3,500 rpm, plus a 15°
vacuum advance at 10 in-Hg (inches of vacuum).
If your balancer does not have any timing marks, MSD offers timing tape kit PN 8985.