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low vacuum

I just bought a vr4 with a few mods, and it seems to have really low vacuum. The car has 272 cams an hks vpc, hks gcc, hks evc. ect. It had a horrible idle surge when I picked it up and I reset the timing and idle and it went away. I did a boost leak test and found a crack in the smim.

I re welded that and it still has low vacuum and tries to die when I let off to idle at a stop light. My question is, could a cam be off a tooth causing the low vacuum and causing it to run funny?


Well-known member
Apr 29, 2001
Yakima, WA
You didn't say what readings you were getting for vacuum, but they are lower with 272's. My car idles at 750rpm and pulls roughly 10in/hg at 1100ft asl.
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