wrx exhaust for a 2.5??

[red22]

Is it really true I can use a cat back exhaust for a WRX on my 02 RS? If so, which would be better (big hp gain, affordable, reliable)
Borla, Cobb or Stromung. As for the Stromung exhaust which mm do I go with --76 or 89?. Also would investing in Borla headers be a significant hp gain? I read average 10 hp and 14 lb/ft. True?!?

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[piker28]

10hp with borla headers is stretching the truth i believe, the cobb headers would prob give you that

wrx exhausts will not work on our cars due to the size of most of their pipings(2.5"and +) the pre 01 rs exhausts will work on your cars though

[DreddRS25]

I own a MY01 RS 2.5l

Took off my axleback and had a shop weld a WRX axleback to my midpipe. (Was going to have a custom midpipe, lack of time and money) Made the exhaust sound a little deeper, and no real noticable gain in performance. Though, the twin tips looked and sounded better then my stock muffler.

Went back to the shop a month later for the midpipe to be put in. They took the flange that connects to the cat and put it on a 2.25" midpipe (no resonator) and welded the other end of the MP to the muffler. Again it deepened the exhaust note, however this time I could feel it accelerate better through the rpm band. No gain...No loss in power, definately smoother. If you go with the whole WRX cat-back then you might lose a little back pressure in the midpipe due to the larger diameter. Stay close to 2.25 from cat-back.

In short a WRX will not hamper your performance nor net you much of a gain. Though, it frees up the exhaust a little and deepens the exhaust sound nicely. Also, you will have to have a shop install it or someone who is very handy with welding.

[elijah25rs]

N/A cars respond better to higher backpressure. I believe that a WRX exhaust will lower that from a stock RS.

Borla headers will not give you that much. Cobb's are more likely in that range.

I would go with the Stromung. Does anyone know the gains for the Cobb exhaust.

[piker28]

Originally posted by DreddRS25
I own a MY01 RS 2.5l

Took off my axleback and had a shop weld a WRX axleback to my midpipe. (Was going to have a custom midpipe, lack of time and money) Made the exhaust sound a little deeper, and no real noticable gain in performance. Though, the twin tips looked and sounded better then my stock muffler.

Went back to the shop a month later for the midpipe to be put in. They took the flange that connects to the cat and put it on a 2.25" midpipe (no resonator) and welded the other end of the MP to the muffler. Again it deepened the exhaust note, however this time I could feel it accelerate better through the rpm band. No gain...No loss in power, definately smoother. If you go with the whole WRX cat-back then you might lose a little back pressure in the midpipe due to the larger diameter. Stay close to 2.25 from cat-back.

In short a WRX will not hamper your performance nor net you much of a gain. Though, it frees up the exhaust a little and deepens the exhaust sound nicely. Also, you will have to have a shop install it or someone who is very handy with welding.

im pretty sure he meant a aftermarket catback made for a wrx not the normal wrx catback

[red22]

where is a good play to buy cobb headers? my search engine couldn't find a place

[piker28]

cobbtuning.com i believe but be ready for the pricetag

[red22]

no thank you!!! pricey!! i think I'll go with the $300 borla header!!!! as for the cat back exhaust--cobb or borla? the borla is for wrx. as for Stromung which one do i want???76 mm 89 mm?
new to the techi stuff!!

[piker28]

do not go bigger than 2.25 piping for your exhaust

and although cobb is pricey you will get the most gain from that header

[Nicklbrso]

Originally posted by piker28
do not go bigger than 2.25 piping for your exhaust

and although cobb is pricey you will get the most gain from that header

Very true and very important

[mycarsux]

ya, i got borla headers, and i can tell you that the most thing u will get out of it is the sound. makes a nice rumble and stuff, but very little if any power gain. as for a catback made for a wrx, i believe the only thing u can use is the muffler because the midpipe is shorter on the wrx compared to the rs (correct me if im wrong). just get a custom midpipe (its cheaper anyways) and watever muffler you want. my whole cat back cost me about 300 dollars (custom midpipe, apexi resonator that was cut off from a different midpipe, and apexi n1 muffler). of course, i got the muffler from apexi garage sale, so i got it for a cheap price.

[red22]

what are some other good mufflers? good deep sound with some hp gain??

[piker28]

-prodrive
-scooby sport
-stromung
-brullen

[red22]

what about a cobb cat back?

[piker28]

thats good to

but if you were moanin about price on the headers what makes you think the cat back is so cheap?

[red22]

I am now looking at mufflers and getting a custom midpipe. Stromung looks appealing, hp gain ad ~350 anyone have a stromung muffler and can give me some reviews

[piker28]

if i were to do it again i would buy the whole catback instead of getting a custom midpipe made but thats just me

your crazy with this hp gain i mean no exhaust will really give you anything insane that youd feel if you want powaaaa look at cams and stuff

[blueimpreza25rs]

or if you dont want to start hardcore w/ cams...high flow cat ...or catless