And yeah, I am worried about the environment. I've spent the past three years of my life studying environmental policy and national law. Driving fast cars is my little fetish, if you will, but I do it responsibly.

Pollution is an inevitable fact of modern living, but if you _can_ do something to limit it, especially something considerate and not that expensive.

Anyways, a good high-flow cat will flow better than most mufflers. In fact, at MOST you'll get something like 1 HP from running a test pipe over a good high-flow cat. You'd probably get more HP in switching from platinum to copper sparkplugs or using 5w30 oil over 10w30...