2.5" or 3" Exhaust???

[knightey]

I am currently searching to upgrade my exhaust....I have already done the basics: intake, hardpipes, SMIC and now trying to decide on exhaust....it is my daily driver so my power goals are moderate 220ish something like that...I have heard that 2.5" gives good low end power and good if your boosting under 10psi (which is my eventual goal) and 3" gives much better high end power....any suggestions and/or advise on which is the better set up....trying to avoid overkill but need more POWER!!!

 

[evilmonkeyMSP]

2.5

 

[mazpro]

3" all the way back. less back pressure is a lot better for turbos.
Back pressure is needed for N/A motors.

 

[20mazdaspeed03]

3" "mazpro" knows whats up

 

[SeR_Cyclops]

ummm well i dont know i think my car is faster with my 2.5 inch cutout closed than with it open, it pulls a little more up top with the cutout open but with it closed i can feel a huge gain (vs. it closed) from low rpm's, so i feel that some back pressure is needed. my system is 2.5 inch down pipe no cats, just a straight piece of steel and it is hooked to the stock catback i hope this helps. but i would say 2.5

 

[junya1985]

I got 2.5 and it is fine kooldino speedcircuit mp3 is running 2.5" and he has about 300 hp

 

[EMPIRE]

I am currently searching to upgrade my exhaust....I have already done the basics: intake, hardpipes, SMIC and now trying to decide on exhaust....it is my daily driver so my power goals are moderate 220ish something like that...I have heard that 2.5" gives good low end power and good if your boosting under 10psi (which is my eventual goal) and 3" gives much better high end power....any suggestions and/or advise on which is the better set up....trying to avoid overkill but need more POWER!!!

I have a Perrin 3' inch exhaust system from the j pipe back if your interested. Shoot me a PM

 

[20mazdaspeed03]

I have a Perrin 3' inch exhaust system from the j pipe back if your interested. Shoot me a PM

That perrin exhaust sounds nasty. i had it for a while then went with the vibrant 3" turbo back

 

[turbolife]

I have a Perrin 3' inch exhaust system from the j pipe back if your interested. Shoot me a PM

PM me details...

 

[Outlawstar98]

I'd say 3" man.

Im going to make a custom 3" exhaust with the HKS Carbon Fiber Muffler laiter on this year once i get enough extra cash laying around.

 

[laracroft]

It doesn't make a difference of say 30hp+. Your biggest drain is going to be the S pipe that it connects to. I had nice gains when I changed out my S pipe, DP and exhaust. I used to have the 2.5 all the way back but still had the S pipe. But now I have a GHL S pipe and 3" full exhaust and I love it. It's a little loud, but it's not "ricey" loud and very functional dyno wise apparently.

So if you're going to keep the stock S pipe, then it really isn't going to matter THAT much if its a 2.5 or 3". The car is still going to be blowing air through a straw.

 

[16902]

Does anybody read this stuff anymore?

http://www.mazdas247.com/forum/showthread.php?t=67805

 

[laracroft]

Apparently only when on the toilet and in need a "light" read. lol

 

[knightey]

Thanks for the input.....I do plan on changing out the down pipe eventually and I do want low end power....From what I am reading so far I guess it's pretty much 1 or the other not too much of a difference at the power gains I am looking to achieve