I have a 2002 LS1 with a Pro Charger and intercooler. At idle I get about 10 psi of boost. When driving normal the psi drops to about 7 psi. When I get on it, it drops to 0 psi. This does not seem normal. Why so much drop? Should it evergo to 0psi? All appears normal, oil level good, belt and pullies good and all the tubing is in place, even cleaned the filter. There seems to be a lose in power.

 

You should not have any boost or very little at idea. But if you are losing pressure and every thing else looks good it could be a charge or intercooler pipe. The best way to check this is to start from the blower and work your way around taking off and cleaning and then putting the connectors back on and then tightening all the clamps back down. This will allow you to check for breaks or tears in the connectors and also insure you are getting a good seal and not leaking boost.

 

i think his gauge isnt working right. i bet its reading just the opposite. the procharger is physically incapable of making that kind of boost at low rpm, so we know the 10psi is wrong to begin with. and IF it was making that kind of boost, the car would never idle. id make sure you dont have something crossed in ur pressure gauge

 

I am going to agree with Specter about the gauge beinghooked up incorrectly.

 

Spec is right i didnt think about but it should be the first place you check. What kind of gauge is it?

 

My gauge is an Autometer. I recently pulled the pro charger off to replace my thermostat and I inspected the intake fins and all looked good. The system sounds normal as well. Maybe its time for a dyno and compare numbers. I even thought that maybe the car isnt getting slower but maybe I am getting use to the power. My first car with a super charger so I really do not know what is normal. When it comes to the idle the car will shut off sometimes. The idle will go up and down then die. It always starts back and then idles about 600 rpm. This may not matter but my charger fits the corvette and so all my pully's are off a vette to make the charger fit. You can view it at cardomain.com and type in 1096ss under search. You will find four of my cars, and yes I am a GM guy.

 

ya im going to agree with the guys about the gauge being backwards.. i have no idea how thats possible. but the centrerfugal super charger wont make 10psi at idel and when you floor it you say the gauge goes to 0psi. that just reinforces the idea that its backwards.whats your boost controler is set at, that would give us an idea what kind of boost you should be making.check your lines on the guage and look at the intructions. also a dyno WOULDgive you real numbers on the boost. also im curios what 10 psi will do for a 5.7Lin HP and TQ numbers, becuse im on the same road with a tt kit for my 77.

 

Sounds like you have a vacuum gage in place of a boost gage. A vacuum gage on a supercharged engine will show high vacuum at idle and no vacuum under boost. Checkyour readingswith a test gage.