
Originally Posted by
Coogles
The 2.5" will be fine. With guys trapping 115 on S&S headers running a 2.5" downpipe, what in the world does anyone need a 3" downpipe coming off of stock manifolds for? 2.5" is plenty large to support the power levels it sounds like you're wanting to achieve. Plus, if you're still running a stock cat-back there's absolutely NO reason to even think about going bigger than 2.5". The 3" section before a small 2.25" cat-back would KILL exhaust gas velocity and create a huge area of high pressure in the downpipe.