Ok, I've got a Comptech SC. I've lost power since I've added a front mount intercooler and gone down to a 3.5" pulley. I'm pushing 5.7lbs of boost at 8500 rpms. This sounds reasonably low to me with a 3.5" pulley. I've done a compression check and everything checks out. No boost leak that I can see. The belt doesn't show any signs of it slipping. What else could cause the low number? I understand the intercooler takes some away, but not that much. I thought the 3.5" pulley should be 8-10lbs?

A compression leak is the only thing I could think of. Any other ideas on what I can look for?

Thanks,
Dave

 

the FMIC install will most likely be the reason with air leaks in the silicone tubings that you place in between each joint of piping. Make sure everything is very tight and then lastly check for any vacuum hoses that may be cut or open.

 

but when I pressurized (sp?) the system, wouldn't I hear it leaking? Or could it be small enough not to hear it. I didn't hear any leaks whatsoever. I was actually thinking the intercooler was the culprit, but wasn't sure how. I installed a 4" pulley before this 3.5" pulley and basically got the same amount of power...granted the temperature was a little cooler with the 4" pulley when I put it on the dyno. Both pulleys were installed with the FMIC. We just took the bumper off the car last week, and I'm absolutely positive the piping is tight, and we ran a compression check before we put the bumper back on. Silicone tubing you mean the cuppling things right? With the clamps?

Thanks for the quick response!
Dave