But I said that to say this, there are different size exhaust manifolds, and we found one of the larger mouth outlets, and ran a true 2" pipe from there through a free flowing muffler. That was a difference we could feel.
Actually, this is not true. All the outlets are roughly 1 7/8". The factory used different sized exhaust pipes. The most common being 1 7/8. The factory Supersix used 2 1/4" to the catalitic converter and 2"out the back. I have used 2 1/4 expanded to 2 1/2 out the back. This reduced ET`s by 2 tenths compared to the factory 1 7/8 pipe.
