I've got the Flowmaster force II catback for my car. It's the one with the single outlet, all 3" piping etc. It doesn't really fit all that well. When I rev the car up, as soon as the RPMs begin to drop I can hear some rattling. Here's a sound clip-

http://speednutz.com/Members/Fastzntn/Audio/750rpm.mp3

The sound clip really doesn't do the car justice, but at least you can hear the rattling.

Anyone else have this problem??

John

 

Flowmasters dont really thrill me, and there quality control seems to be going down hill, i know about 3 people who have actually had to have exhaust shops rebend the "custom mandrel bent" pipes cause of rattling and plain out not fitting on the car right.

 

Yes, I agree. I bought the American thunder for my Z, and it was a pain to put on. My over axle pipe rattles on teh floor board I think. Either way I have a rattle. Not too impressed with the sound either.

 

I have the American Thunde also. I managed to intall it without any rubbing the first time. I didn't have it tack welded and eventually moved and started rubbing. Beating on it with a rubber mallet solved the problem.

 

Well I think mine sounds ok. I'm looking for something a little quieter now that the cam is in. I think what I'll do is have a guy I know that does exhaust work use whatever of the flowmaster I pipe that he can, and put a magnaflow muffler on it. The pipe going over the axle is what is rubbing now. I was also wondering if that would cause false knock, but nobody seems to know, and I don't have a scanner or anything for the car so I can have a look.

John

 

My american thunder flowmaster sits too close to the driveshaft and comes in contact when the car is jacked up. I have had to bang a dent in the pipe to make some room.

It also could use to be about an inch closer to the y-pipe, I also get the rattle on the crossmember.