Bought a VAC gauge, and it seems I'm getting around 10 inches of vacuum at hot idle (950). LE heads, 233/239 .570 lift cam, 112 ls. Is this normal? In the process of tracking down a LOT of missing power (Car ran 12.72@107 best with mods) Trying to rule out everything I can... and from what I've heard, this is pretty low. Experts give your opinions.

 

Very low, maybe try a vacuum pump. Also, I could be wrong but the specs on the cam you are using seem to be for a blower.

 

Its not a blower cam Just trying to figure out of this low vacuum is an indicator of a certain problem somewhere else.

 

I don't know if this will help, but my Hotcam and ported heads draws 14" of vacuum at 850rpm idle.

I would expect a cam like yours to draw less, so I wouldn't be surprised if it was pulling only 10".

However, someone with that setup should be able to give more light on what it should draw for you..

-Dave C. '97 Z28

 

I've got a slightly bigger cam in my black car and am pulling about 9-10 at 800 Idle RPM and about 12-13 at 1050 Idle RPM at operating temp. Yes, I have two different tunes that have different idles set in them that I've run since yesterday, if anyone is wondering.