Re: How Important is OMC Ignition Timing?

[legendre]

quote FrankR:

The factory service manuals say to have it at WOT, but the fact is it really doesn’t matter. The only reason I can see for saying to have it at WOT is that would hold the armature plate steady while you are messing with it.

Ah of course! You’re right, it doesn’t matter – as we’re only concerned with the angular relationship between the armature plate and the points cam on the crankshaft.. how far one leads or lags the other.

What matters in this case is the angular displacement of the armature plate from the crank position. If the plate moves, the crankshaft would be moved to reestablish alignment of the marks, or vice-versa.

Actual position of the armature plate is only of concern if we’re measuring timing angle with respect to TDC, which is a fixed point of reference.

Thanks for catching my blunder! Very much appreciated.