Well, I got the Mufflex exhaust on the other day and I decided to change the oil(break in stuff) and filter, and start her up. I was really excited to hear what it was going to sound like with the new exhaust. Now, the first time that I ran the car, it was open header. I have a 420+ HP 350 with Hooker Super Comp long tubes so you know it was loud. But when I started it up yesterday, the engine was still loud. It didn't sound like an exhaust leak. I'm using the Mr. Gasket copper seal exhaust manifold/header gaskets that have that sealing ridge in them. I am using Percy's softseal collector gaskets, and the rest of the Mufflex 4 inch exhaust is secured with their supplied band clamps. With the hood open, the engine makes so much noise that you can't really even hear the exhaust that well. Now, I have heard some sound clips of other f bodies with the mufflex, and this thing should rock. Something isn't right, but I don't know what. I know what the open headers should have sounded like, and it was pretty close to that with mine being a little tinnier sounding. But this engine is so loud that I think that I will get pulled over if I try to drive it. Any suggestions/opinions? Thanks, Paul Moore