M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Swaps, Turbos, Buildups => Topic started by: Danny318 on December 04, 2012, 06:35:34 PM
-
Just wondering how much vacuum you pull at idle. I figure the dasc would make there be less vacuum than stock.
I only looked real quick and mine looks like 12-15 hg/in (or whatever the unit).
Seemed low, so it either could be low because of the hot cams I got in this motor, some leak, or restrictive tubing for the gauge. Or its totally normal.
Let me know what you get for numbers (and any mods you may have that influence them)
-
Sorry, I don't have a vacuum gauge. Since the SC is bypassed at idle, I'd expect it to be similar to stock.
-
Sorry, I don't have a vacuum gauge. Since the SC is bypassed at idle, I'd expect it to be similar to stock.
It should read same as stock because of the bypass valve... You can also check your afr if you are running little leaner than stock. If it is then your bypass is not working correctly and that could explain a higher psi at idle (even still in vacuum)
-
Thanks guys, thats right. SHould be about the same.
I'm thinking the cams have something to do with it.
AFR at idle is good (14.7ish) and i couldnt find any vacuum leaks at all.
-
Any other people ?
-
Hot cams will definitely impact vacuum at idle. The hotter the cams generally the less vacuum at idle.
Cars with very large cams sometimes use a vacuum reserivor to rin accessories that require vacuum such as brakes.
-
Hot cams will definitely impact vacuum at idle. The hotter the cams generally the less vacuum at idle.
Cars with very large cams sometimes use a vacuum reserivor to rin accessories that require vacuum such as brakes.
Good to know!