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**MySons68C20** · 03-13-2023, 10:40 PM

With the vacuum advance disconnected you need to see 34-36 degrees total mechanical advance all in by 3000 rpm. Do you have a timing light?

03-13-2023, 10:40 PM	#6
MySons68C20 Senior Member Join Date: Sep 2014 Location: Wenatchee, Wa Posts: 897	Re: Cam choice? With the vacuum advance disconnected you need to see 34-36 degrees total mechanical advance all in by 3000 rpm. Do you have a timing light?