supercharger problems...

i just recently had to do a motor swap for my pontiac grand prix GTP 3800 VIN 1 motor. my supercharger doenst work completely. i got 2 or 3 bars on the digital gauge and after i replaced the vaccum hoses i now have half. i have no idea what could be wrong with it so i started throwing parts at it. i do get some boost but not all of it. could it be the map sensor? how do u know when the bearings are going bad on the supercharger? the new motor did come from a buick regal...could it be a loose belt from a different sized crankshalf? please help!

Welcome to AF.

It would help to post the year of your GTP and the year of the Regal the motor came out of.

Bad snout bearings will normally whine. A bad coupler rattles.