Exhaust...2.25 or 2.5in and over or under axle??? Options

[Davesceli]

Which is better for a stock 5sfe, 2.25 or 2.5in pipe? I've searched around and its a pretty even split on opinions between them. I've decided on the HKS Carbon TI muffler with the 60mm (just over 2.25 in) inlet, i know its expensive for a stock motor but it looks damn good and sounds sweet, my mind is made up. Carbon fiber is just so sweet!!!!

Now i just gotta decide what size piping, its gonna be catback, and whether or not to go under axle or over. What are the pros and cons of each??? If i go "under axle" will there be any clearance issues since my car is lowered???

i know this question comes up a few times, but im looking for a definative answer...i've searched alot and i still can't come up with a good answer.

[playr158]

ideal would probably be 2" to be honest.. and go over or under the axle you won't notice a difference..

Although.. Our resident Engineer Dan seems to think differently

you won't notice it on an ass dyno no. but there is an actual difference...length wise its shorter, and flow its smoother, why? because less bends = faster and less restricted flow...