I have a '96 Riviera with a supercharger with 120k miles. I have lack of power around 30-45 MPH. Last year I noticed the sc making a grinding noise like a bearing. I replaced the snout and it calmed it a little but same power problem. This morning I took off the air intake large hose and exposed the screen that introduces air to the sc. When I started the engine it made a metal to metal scraping sound like the blades were metal to metal. I sprayed carb cleaner in there and it calmed a little but it doesn't sound right? Any suggestions? Is there a way to check the boost? I am thinking that the sc is not working properly?
Thank You-Mickey O'Donnell

You must have a bearing problem in the front or rear housing. If the rotors are rubbing the housing, you will have to replace the S/C. You can check boost with a boost/vac (pressure/vac) gage by installing a "T" in the vacuum line under the snout & front of intake. Not much need of checking it though, if you already have worn rotors & housing! Check Ebay for a replacement. Be careful and look at warranty, number of sales & reputation before buying.