[Slow1500]

I was told from the chevy dealer that a cat-back system and air intake system will not void anything. I just put on a magnaflow with turndown and ordered a K&N kit. Magnaflow is a straight-through design and pretty high quality. Plus it sounds good whether on a I6 jeep or a v8 truck. It all depends on how loud you want it. I don't think that muffler has anything to do with emissions does it? Your cats control that.

 

[Slow1500]

Another thing I learned from the Grand Prix community is that when you do a mod like exhaust or intake or whatever that you reset the pcm(undo neg. battery terminal) for an hour or so. It forces the pcm to reset, recalibrate(learns) itself somewhat to the new mods. ..Note, it's still not like reprogramming, but still helps.