Thread: What size exhaust pipe?

I am new to the forum and havent been able to find an answer. I have a 91 se-r and i am going to put on headers and straight pipe to a greddy muffler. I got a 60mm inlet would 2.5 inch piping be too big. Will there be enough backpressure?

2.5" is perfect for N/A
3" for turbo

I have 2.5" on mine and love it

Even with no cat?

Even with no cat?

Don't run straight pipe, you'll loose power if it's a stock engine(internally).

Give this thread a read - http://www.sr20-forum.com/all-motor/53021-straight-pipe-de.html

Here's an excerpt - (Post #17 of the thread)

Interesting. On my VE, for exhaust I run a JMR header to a 3" exhaust to magnaflow, no cat at all. The car made 206hp at the wheels on the dyno. It is loud as phuck. Are you guys saying that adding a cat would increase my bottom end? Besides N1 cams the engine is stock.

No. We had an n1 cammed vvl stuck at 196whp. Took out the cat and the car made 202whp, gains were across the graph. No other changes.

Thanks for the link Sentraga.