Technical information

AUTOTRONIC CONTROLS CORPORATION • 1490 HENRY BRENNAN, EL PASO, TEXAS 79936 • [phone] • FAX [phone]
www.msdignition.com email: [e-mail]
99
PROGRAMMABLE
TIMING CONTROL PN 8981
The MSD Programmable Timing Control allows you to program an advance curve for engines with locked-out
timing. It is a programmable electronic version of a centrifugal advance. There is also an optional single stage of
retard and 20° start retard.
The timing curve is programmed with three locking potentiometers. When all of the pots are turned to full clock-
wise position, there is no timing curve. This is where you should begin all adjustments. The total timing must be set
in the engine before beginning any adjustments.
Retard Stage
There is a single stage of retard that is activated when the Gray wire is removed from ground. The amount of
retard is adjustable with plug-in modules. When the retard is not being used, the Gray wire MUST be grounded or
a Zero degree module must be installed.
Gray: When this wire is removed from ground, the retard stage is activated.
Red:
Black:
Yellow:
Connects to switched 12 volt source.
Connects to ground.
This is the trigger output to the Ignition. It will connect to the MSD’s White wire or Points
terminal.
White:
Violet and Green:
Connects to points or an ignition amplifier output. When this wire is used the Magnetic
Pickup is not (Violet and Green).
These wires are routed together in one harness and form the magnetic pickup connector.
This connector plugs directly into an MSD Distributor or Crank Trigger. The Violet wire is
positive (+) and the Green wire is negative (-). When this connector is used, the White wire
is not and should be sealed.
General Wiring
Trigger Wires
Start Retard
When 12 volts is present on the Violet wire, the timing will be retarded 20° during cranking.
Violet: Activates 20° of retard when connected to 12 volts. Connect to the start side of the starter
solenoid wiring.