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Ignition Timing Connector: Description and Operation

In-line Connector With Shorting Bar:






PURPOSE
The octane adjustment switch is used to retard the ignition timing approximately three degrees to reduce detonation due to use of lower grade fuels.


OPERATION
When the switch jumper is INSTALLED, the computed timing is normal. With the jumper REMOVED, the timing computed is retarded approximately three degrees. This is done to allow for optimum spark advance for effective combustion of the air/fuel mixture.