Exhaust Manifold -- engine lift?

[mimregi]

I was prepared to go 2.25" (no resonator) based on feedback here, and if not for the shop's encouragement to go 2.5" (no resonator), which I had assumed would be louder, but I cannot imagine it being much quieter.

[shamus11]

Here's just a little handy hint, when putting the exhaust gasket on, grease both sides with a moly grease, this will stop it from sticking to the head or exhaust and destroying it the first time you take the pipes off!

[shamus11]

As for pipe size I've been told by a well respected mentor that on N/A cars the exhaust works like a siphon. There is an ideal diameter where the air flowing out the exhaust helps pull the air behind it out. Too big and this won't happen.

On a near standard 6 cylinder car 2inch is plenty. 2 1/4 is normally cheap for mufflers etc, 2 1/2 sounds too big to me.

If you want to quieten it down put in a triple flow muffler. Don't use straight thru's.