Procharger with little boost
If your bypass valve has too much of a gap when closed, you won't build a lot of boost. There will be a little bit of a gap between the butterfly and the bore when in the closed position, but if there is more than a 1/16 of an inch, then it can leak too much boost through it.
How tight do you have your blower belt? A new belt needs to be broken in and after a half hour of use or so, it will stretch and it much be retightened. If you see any belt dust on the blower housing, then you are probably getting slippage. The belt has to be a lot tighter than you would normally have for other accessories. Bob


