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[augidog]

Does the distributor shaft speed correlate with engine rpm in any way?
I am trying to tune my advance curve.
Thanks
_________________
1978 924 95 mile daily driver.
Audi TB/POR174M/High Flow Cat/2.25" exhaust
I knew that positive thinking thing wouldn't work.

[1982Porsche924]

Since the crankshaft makes 2 rotations for every turn of the camshaft, and the distributor runs off the camshaft, I would assume that the distributor shaft spins at 1/2 of the engine's RPM.
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1979 Porsche 924 "S"
Engine: Euro pistons, Light Flywheel, Weber TB, Bursch Header, Cam Wheel
Suspension: Front coil-overs, adj sways, Solid bush. Thicker tors. bars, 5-bolt, BBS rims
Body: Fiberglass widebody kit, 931 Nose

[augidog]

It makes sense.
In the Haynes manual the full advance curve is about 2250 rpm for the distributor shaft speed.
With the engine rpm being double, that brings the rpm to 4500, which is the set speed for the full advance test.

With the above in mind:
With my vacuum lines disconnected, I should see the full advance reach its peak at 2250 rpm on the engine with my timing light.
Is this correct?
_________________
1978 924 95 mile daily driver.
Audi TB/POR174M/High Flow Cat/2.25" exhaust
I knew that positive thinking thing wouldn't work.

[Roger]

If I understand it correctly most of the advance is mechanical so you might not see full advance at 2250.
_________________
1981 924 NA

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