I think it's 2" but I'm not sure. But how much boost do you think I can run before the exhaust chokes it down too much? I'm at 10 right now. Should I even try to go higher?

lol well the stock is 2.25 i believe with press bent which slows it down alot... haha but yeah i wouldnt even boost to tell you truth with out an exhaust... but thats just me, dualgen is boosting with stock catback but dual exhaust, so if you ask me, i would get a pacesetter and change the muffler or get a apexi turbo exhaust i like the way they sound

stock exaust is good for about 200HP. 2.5" exaust is good for around 300-325 HP. Its NEVER a bad idea to run a larger exaust, mild boost or high boost. With a turbo, larger is better.

I used to have the EVO 3" catback exhaust, and it FLOWS! However, right now, I have the stock GS-T 2.25" catback back because I'm waiting on the QTEC (exhaust cut-out valve). I can personally tell you the difference is night and day!

The stock exhaust is soooo restrictive. My 16G doesn't even spool up until around 4k+ RPM's. The real difference is on the freeway. Before, when I go WOT on the freeway from 50-60 MPH, my car will just take a leap forward. Now, there's a "lag." If you're planning on boosting more than 10-12 PSI, the stock turbo exhaust, or stock RS/GS exhaust isn't any good. I can't wait to get the QTEC installed :(

Alright I guess I'll just keep it at 10psi until I get the exhaust done. Thanks for the input.

actually inner diameter is just a tad under 2". Afterall it is inner that matters right...?

I noticed a large reduction in EGT signature when after installing my RSR from my old pacesetter as well as my GST exhaust.

>Alright I guess I'll just keep it at 10psi until I get the exhaust >done. Thanks for the input

do your yourself a favor and buy a data logger and some fuel upgrades too. Just thinking of your kids college fund. ;-)

Daren

I have a datalogger, SFMU, 315cc injectors, Walbro 255HP, and I'm getting an inline pump that flows 40GPH @110psi.