Vaccum on a 2000gt at idle?

I'm seeing right at 20#s of vacume at idle and 25/26 when I get off the gas with the clutch out.

This is on a P600B with the 2.9" pully, it's only hitting 6#s of boost at 5K. Is my gauge wrong? I just got it and it's used, but this is my first supercharger, so I wasn't sure what to expect.

I heard most guys see 8-10# with this pully on this kit. I figure either the gauge is wrong or I need a new bypass...I hear the stocker is prone to leak.

Thanks for the help, guys!
-Jonny

Guage seems to be fine.

As for the boost you may have a good flowing setup or getting belt slip too.

Or are the 8-10 psi #'s your hearing at 6,000 rpms or the 5,000 you say you see your 6psi? That extra 1,000 RPM's may be the difference of 2-3 psi.

Yeah, I'm seeing 6psi at 5500, and I think most guys figure at 6K. I have the 3.125" pully, so I'll drop to the 2.9" That should get me there, I think.