Bart, Like Zmefly said, you won't gain any HP with a header (unless you really build up the engine), it will only make it louder and headers tend to rust. Exhaust systems bought from MSA or similar place never seem to fit quite right. I suggest you go to a good muffler shop and have one custom bent for you. It will fit better, you don't have to go through the agrivation of getting rust in your eyes, and it might be cheaper in the end. I kept the stock manifold, had 2 1/4 pipes custom bent, ending with a nice turbo muffler. this was about 4 years ago, but I believe it cost me $126. The car breathes much better, sound agressive, without being obnoxious. Well, that's my two cents worth. Marty