[MarinosMadmen]

Originally Posted by Can'tHave2MuchHP

Oh yes it's very noticeable lol. Headers + High flow cats is quite a bit louder than stock. Headers + no cats is ear splitting when under acceleration. Exhaust is best done in stages so first I'd order the Headers and with cat-less connection pipes or High Flow cats depending on how loud you want it, get them installed, see how you like it sound wise, and if you think you want more then there's a couple out there, but Corsa's ZL1 system is probably the best, no drone, plenty of voice, quiets down when you're cruising.

So the ZL1 has what's called a dual mode exhaust, abbreviated part number is NPP which is what everybody uses to refer to it. Dual mode exhaust has an active baffle in the back to open and close either side of the muffler. When the car is stock on the ZL1, the baffle is open (loud mode) when the car is at Idle, then it closes when you're driving under 3500 RPMs, but if you accelerate/rev to above 3500, the baffles open up and the car gets much louder. Pulling the fuse gets rid of the open and close mechanic and is open all the time. I'd say that 90% of the modded ZL1s still have the stock NPP exhaust with the fuse pulled, with or without headers/cats.

F8 exhaust fuse pull is easy to do, it's located in the trunk of the car under the carpet on the passenger side. Here's the thread on it: http://www.camaro5.com/forums/showthread.php?t=268970

Thanks man you have been a huge help I appreciate it.