I know i need a 80s series muffler for my 1999 sse, what size is the inlet and outlet on it? Or if i were to order off flowmastermufflers.com, which options would i pick? ( it says they only offer it for chevys, and pontiacs, but when i click on the pontiac option, it says they only offer it for firebirds.) a part number would be nice if anyone knew what it was.

I believe the exhaust is 2.5" all the way back. Most of the 80 series i've seen is 3" in and 2x2.5" out. When i get mine i plan on just putting a 3" to 2.5" reducer in to make it work.

Not sure if I remember right, but I think mine is 2.5" in and 1.75 out.

yup that'* what i did with my borla muffler. not too hard at all.

thanks guys