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jimfulco · 05-17-2007, 10:56 PM

Some race motors can benefit from vacuum advance. It won't do squat at full-throttle on the track, but it can help it run smoother and cooler in the pits.

I had a 292 with a 310* cam in a Nova for a short time, and hooking up the vacuum advance (manifold vacuum, please) made it run smoother at low rpm, such as in residential areas & school zones.

Ported vacuum was introduced for smog devices, and the HEI distributor was designed as a smog device. Recalibrate it like Crazy said and it should work much better. Just don't tell the smog police.

05-17-2007, 10:56 PM	#31
jimfulco Registered User Join Date: May 2003 Location: Shreveport LA Posts: 3,170	Re: vacumm advance question Some race motors can benefit from vacuum advance. It won't do squat at full-throttle on the track, but it can help it run smoother and cooler in the pits. I had a 292 with a 310* cam in a Nova for a short time, and hooking up the vacuum advance (manifold vacuum, please) made it run smoother at low rpm, such as in residential areas & school zones. Ported vacuum was introduced for smog devices, and the HEI distributor was designed as a smog device. Recalibrate it like Crazy said and it should work much better. Just don't tell the smog police. Last edited by jimfulco; 05-17-2007 at 10:59 PM.