GM HEI Dist. Vac Adv line to ported or constant vacuum??

Dec 27, 2003 2 Replies

I have a Stock mid 80's 305 with headers and a vac secondary holley. My questions is what port do I connect the vacuum advance line to, Ported vacuum on the carb or manifold vaccum. And how do I set the timing.


Thats where I had it, my misconception was the motor could not handle total advance of around 49° at 2500RPM. After searching the internet I found it can. (Keep advancing till it pings) So I once again connected it to ported, reset the timing to ~ 12 base. Resulting in 49° total. Powered is restored and it runs well.

Thanks for the info.

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