upgrading exauhst how big of a pipe 2 1/5" or 3"?

[cronot07]

i'm considering putting on an upgraded exauhst system on i was wondering how big of a system pipe should i put on 2 1/5" or 3" pipe let me know what gives the best results..

 

[InferiorWang]

Originally posted by doug
3" exhaust is way overrated on this board, IMO. The argument of "just get 3" so you won't have to upgrade later" isn't a very good one, to me. 95% of the people here will never outgrow a 2.5" system anyway, but will have to put up with the extra noise, possible boost creep, and maybe some scraping of the exhaust piping that hangs too low to the ground.

Until you start putting out major HP and running 11s or better, you won't really gain any significant performance from a 3", but that's just my opinion. I'm still looking for someone that's willing to do some back-to-back testing of 2.5" vs. 3" on the same car either on a dyno or at the track to see if this is true.

nice to see someone who thinks the way I do. There are too many people that think 2.5 becomes a restriction much earlier than it really does. Yes 3" will flow quite a bit more, but will you need it. Or can u justify spending the extra $$$ on it? Some back to back dyno's would be nice so we can see where it really makes a difference.

 

[Margul]

Yeha I agree with the 3in exhauste being overated too. The numbers I put out speak for themselves. The reason people have crap performance on 2 1/2 in piping may be because its not a very thought out setup. Take time on your exhauste especially with a turbo car.

 

[doug]

Exactly. That's why my 2.5" is a mandrel-bent O2 eliminator system.

 

[midnght]

Thanks for the reply Doug! I am still a ways back from getting my exhaust but still looking at all my options!