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I have been working on ignition timing and can find ample information about timing values for mechanical advance.  For example, 16 degrees initial and 36 total advance, all in by 3000 rpm.  Similar information for vacuum advance is a little scarce for the 351C motor.  There is ample information about vacuum advance for the Small Block Chevy but not for our cars.  Any insight you have is appreciated.

I am concurrently working on two cars.  One has a Duraspark distributor and the other has an electronic distributor.  The Duraspark is currently adding 15 degrees vacuum advance at idle.  I used an allen wrench to adjust the pod to that value.  With the timing light I can see the vacuum advance fall off when I blip the throttle.

Here are the settings for the electronic distributor.  The vacuum advance setting of 8 degrees is their default and I left it there while working through this.


The table below shows the relationship between vacuum and kPa.

Here is the generated table.


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