i was thinking about getting my own custom exhaust, buy just buying a muffler and having some body shop put on some pipping, but i wasnt sure how thick the piping should be?? any idea??

what would the best piping be for my car for the most permance?? 5s-fe

2.5" inches should be fine. And if you are talking about thickness of the pipe itself. Measure what your stock pipe is and go with that.

Damn dude.... go for the 3"...that's what i have on the end of my Greddy SP...it's bad ass....sounds like a ****load of work to do custom tho....good luck with that ****

?? the greddys catback piping is 2.25". i think the tip may be a full 3"... anyways 2.25 is plenty, if you are going into moderate modifications under the hood on your 5s you should probably go 2.50" and get a highflow cat or replace it with a testpipe. 3"+ and youll run into backflow problems. my friend got i think 3.5" piping on his eclipse and he has major backflow problems, his car is considerably slower than it was before the exhaust system. he has no worrys though because hes going to turbo it this year. all im saying is without FI youll have problems going 3" or bigger...

--K2_Celica+Jan 5 2003, 10:11 AM

QUOTE (K2_Celica @ Jan 5 2003, 10:11 AM)

?? the greddys catback piping is 2.25". i think the tip may be a full 3"... anyways 2.25 is plenty, if you are going into moderate modifications under the hood on your 5s you should probably go 2.50" and get a highflow cat or replace it with a testpipe. 3"+ and youll run into backflow problems. my friend got i think 3.5" piping on his eclipse and he has major backflow problems, his car is considerably slower than it was before the exhaust system. he has no worrys though because hes going to turbo it this year. all im saying is without FI youll have problems going 3" or bigger...

yep. 2.25" is as big as you need on a non-turbo engine.
-John-

thnkx guys, but the muffler i just bought is 2.5" inlet so i will just go with that.

--94gtcelica+Jan 5 2003, 11:09 AM

QUOTE (94gtcelica @ Jan 5 2003, 11:09 AM)

thnkx guys, but the muffler i just bought is 2.5" inlet so i will just go with that.

Good choice. I have 2.5" piping on my car and I felt a power gain over my stock piping.

On a related note, I was reading January's Import Tuner today on my three hour trip home, and they put a 3" mandrel-bent exhaust system made for the SR20DET on a 2.4 liter 240SX without forced induction, and they still gained a little bit of power and a little bit of torque. I thought they'd lose power or torque, but I was wrong.

go with either 2.25 or 2.5. i had mine done custom with 2.25 and it sounds great. make sure they dont leave any resonators in when they do it. mine turned out louder than i expected, it sets off car alarms when i drive by and is only costed $340 and was done in about an hour and a half