I have a couple s2000 muffleres laying around and I am contemplating putting one on my coupe, I also have the s2k resonator so I can use larger exhaust piping. Now, should I go any larger than 2 1/4 pipe or would larger put me in the loss of back pressure range. The reason I'm doing this is because if I go spend $300 plus on a cat-back system, the wife will make me sleep on the couch. I also have a buddy that works in a muff shop and he's going to build my cat-back for $60! Any ideas or comments would be greatly apprereciated! Tahnks!