1fast97gsx
20+ Year Contributor
- 4,517
- 17
- Jul 6, 2003
-
Orland Park,
Illinois
I know this has been discussed before, but no solid numbers were shown. I'm wondering what sort of vaccum at idle people are getting with 272 cams. I would prefer to know this on a 8.5:1 motor and at 750 rpm. If you raised your idle please let us know the new idle number. The reason I ask is I'm only pulling around 10 mm/hg at 750 rpms. I have a very small vaccum leak in one of the intake manifold welds, but I find it hard to believe that a post throttle plate pinhole smaller than a needle could cause this. Perhaps 10 - 12 is also normal so that's why I ask. 
