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What Size Exhaust?

bhiggs89

Veteran CEG'er
Joined
Dec 23, 2007
Messages
706
Location
Peoria, IL
So I am thinking about upgrading the stock exhaust on my car. But I dont know if I need a 2.5" or a 3" exhaust.

My car currently is completely stock, except for the turbo. I do have headers sitting in my room waiting to be put on.

My Dad's car has a 3" exhaust, he has a 3L-Turbo. Sometime down the road I am thinking that I will also have a 3L-Turbo, but do I need a 3" exhaust?
 
with an NA car 2.5 or a free flowing 2.25 system is good. Larger exhaust will lose you horsepower because there is less scavenging and more turbulence. But this is when you are talking about NA.

With forced induction, bigger is better (within reason). 3" would be good.
 
As everyone recommended, 3" is perfect for your application.




 
exhaust.JPG


here is what the 3" looks like, (my muffler failed so i had to remove it). but the problem i had was, when the suspension travels, it collides with the rear control arm. and since the pipe is so large, there is nowhere else for it to go. you can hang it lower, but then you run the risk of it hitting the ground on not so level terrain.

edit: i dont think mine was ever mounted properly which could be the reason it was colliding. i dont see how a 2.5" would be any more out of the way.
 
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