Boost Gauge

[TurboXT]

When the car is off my gauge reads 2 inches of vaccum. so does this mean its off by 2 bars even when the car is running?

[Subliminal]

Maybe.

I had one that read 0 psi when the car was off, and maxed out at 5 psi when in boost and never went into vacuum.

But yours sounds like its working a little better, just off a tad. Maybe adjust the grainger so the car will hit overboost and see when it does it..?

[TurboXT]

well i hit overboost sometimes on 12. so maybe it is off by 2