3" or 2.5"

[me_2_3_5]

If i am running a 2.5" swing valve, will i gain anything by running 3" exhaust or will 2.5" exhaust do just as good???

[2.2turboscotty]

some may have other thoughts on this but i ran 3" from the dounut gasket into a bullet style muffler under the car and then a 80 deg. bend out the side in front of the l/r tire and i love it! i felt i got a good gain over my 2.5" that was running out of the back in stock location. i would not change it at all. and by the way no cat probably helped some.
scotty

[tryingbe]

You know, the question you should ask is, "Do you want more torque and more hp or not?"

Go for the 3 inch.

[Dustin Imports]

Quote:

Originally Posted by tryingbe You know, the question you should ask is, "Do you want more torque and more hp or not?" Go for the 3 inch.

Hahahaha

[detobias]

IMO justifying the extra cost, weight & hassle of installing a 3 ilo 2.5 primarily depends on what *other* mods you have made or plan to make - or to put it another way, what Hp level you are shooting for.

tell us more what the car current mods and your plan ... ?

if your plan a mostly stock package including the 2.5 SV, and not planning to go over 18-20 psi ?? , then IMO 2.5" is fine; additional gain of 3" not worth it

my plan : 2.5 TII, cam, flow work on head, intake mani, exh mani, .63 turbine housing, ... therefore I will get a 3" SV and exhaust to match

[me_2_3_5]

I'm putting a 2.5L, board 40 over, minor head work, upgraded turbo, planning on boosting around 7 on the street and 22-25 on the track.

[86lance]

2.5 inch will sound a bit raspy and poppy where a 3 inch exhaust is a little bit more mellow and thumpy plus it doesnt pop on decel,at least from my experience

[detobias]

Quote:

Originally Posted by me_2_3_5 I'm putting a 2.5L, board 40 over, minor head work, upgraded turbo, planning on boosting around 7 on the street and 22-25 on the track.

if that is your ultimate plan then the 3" will be a worthwhile change and certainly wont be the 'cork' in your build-up... good luck !!

FYI - I am currently running a 2.5 SV, 2.5 DP, 2.5 -> 3" flowmaster cone, no cat, no muff, then full 3" back to bumper (Omni) ; its not *too* loud but I wouldnt want to do highway driving withgout earplugs and does sound nice and deep

[tryingbe]

I drive with my 3 inch downpipe and cut-out on the freeway.
It's quiter than when I drive it on the street.

[krazy4]

3 inch