Spark Instant with Crankshaft/Camshaft
True, when I "tune" the Spark Instant, I first REMOVE (lower) spark advance, watch for a major power reduction and STOP the retarding, then I add back 1 or 2 degrees.
Now, a "tip" for understanding the Spark Instant difference in an engine with "crank-fire" DIS vs "cam-fired" Distributed Ignition.
Lets state a know good value of 36 degrees Advance with the Distributor. (Distributor Triggered)
The same Spark Instant event would take place with a 32 degree Advance amount WHEN a Crankshaft Ignition is fitted. (Crankshaft Triggered)
This result is from Timing Chain/Timing Belt stretch.
Lance
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