Author Topic: Measuring dwell angle  (Read 1613 times)

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Measuring dwell angle
« on: November 04, 2010, 07:19:44 am »
Here is a video of a procedure to measure the dwell angle of both the points and the new PAMCO electronic ignition.

This setup is a CB750 points plate mounted on a test fixture with a points cam continuously rotated by a variable speed motor. The points are actually driving a coil, so the resultant dwell measurement is dynamic.


The scope shows the on time (low part of the trace) as 53% of the total time between pulses, which equates to a 190.8 degree dwell angle with a points gap of .014. Although I had run the points in this manner before, I did not previously calculated the dwell angle and I erroneously stated that the dwell angle was 97.5 .

Here is a similar setup for the PAMCO electronic ignition:


The scope shows a 33.333333% on time for the coil, which is equivalent to 119.9999 degrees of dwell angle. The dwell for the PAMCO is derived by the 120 degree spacing of the trigger magnets on the rotor.

« Last Edit: November 04, 2010, 09:14:08 am by pamcopete »

Offline TwoTired

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Re: Measuring dwell angle
« Reply #1 on: November 04, 2010, 01:34:05 pm »
Thanks for posting that.
Lloyd... (SOHC4 #11 Original Mail List)
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