Ok- I have a 06 G6 GT coupe and I want to replace the stock muffler with a flowmaster or dynomax performance muffler (would do the whole exhaust but don't have the cash, just want to add some rumble right now) SO- I looked under at the stock muffler and it's set up kind of funny. so 2 questions: 1. how does this work? How can i put a performance one on there? ( a friend is doing it for me to save money) and 2. what size inlet is it? 2.25? I really appreciate your help!!!!

Yea you can just replace the stock muffler with whatever one you want. Just cut off the stock muffler and tip and wield it back together. There is a resonator also so u might want to replace that with a piece of pipe. The stock pipping is 2.25.

ok sweet...thanks for the info