ILiveAgain

iTrader: (1)

Hey Guys,
Just some quick background: i have a 03 rex, and I'm not really into pimping my auto. If i do mod, i like genuine parts and dont really like dealing with 3rd party aftermarket stuff.
That being said, i would like to install an STi axel back, purchase a catless DP and purchase new gaskets. The borla exhaust, which i believe is a optional Subaru part, is a bit to pricy for me, and i like the look of the STi axel back. TO the point, I'm a newb with subbies and i didnt know if i needed a cobb accessport to go along with my exhaust modd.

subie OCD

iTrader: (11)

For the 02/03's you dont NEED the AP, but it will take advantage of the bigger pipes and give you some more power. I would put in a catless uppipe first.

sneezerboi

iTrader: (9)

If you have a catless DP and just an axleback, you'll probably want to change your midpipe as well. That will choke the airflow from your DP making your slightly larger axleback about as useful as your stock one.

I'd recommend going for a full turboback or catless DP w/catback exhaust, preferrably with a catless uppipe as well.

WRBWRX2002

if he just wants the dp and the sti axel back that should be ok cause the wrx and sti mid pipe are the same if im not mistaken, i have a catless dp and the sti catback on my 02 it sounds perfect, its just loud enough, but doesnt draw attention

sneezerboi

iTrader: (9)

Here's another suggestion. Go with a catless DP and a Borla Hush catback exhaust. It's pretty quiet and has the stock look (not a huge obvious cannister) complete w/the twin tips. You'll have a full 3" turboback.

I guess if you're not going to go too extensive w/the mods then keeping the stock midpipe would be alright, but then you're not utilizing the potential of the catless DP (most are 3" in diameter).

If all you want is the sound and the look, then the STi axleback helps a *little*.

1sicwrx

iTrader: (5)

If he is getting a catless dp and up-pipe, won't he need an Accessport to bypass various exhaust and emissions sensors that would cause CEL's to come on? I could be mistaken but I thought that was one of the advantages of having the AP.

ILiveAgain

iTrader: (1)

Besides the 2.25" vr 2.5" axel back, what are the other exhaust differences between the WRX and the STi?

subie OCD

iTrader: (11)

There are two CEL fixes. One for the uppipe which is a 2.2k ohm resister that you put into the egt sensor, this gives the ecu a constant reading. The other is for the rear o2 sensor. Basicly you weld/bolt an extension for the probe so that its further away from the exhaust gases and reads lower. I dont have the ap, so Im not too familiar with its reflash. However it does have a built in CEL reader/scanner, thats a great tool to have.
WRX axleback is 2.5" also.

ILiveAgain

iTrader: (1)

does anyone know of a company that sells a 2.5" catless downpipe? or a 2.5" 3rd cat delete?

subie OCD

iTrader: (11)

If you want to keep your oem axleback or use an STi axleback, take a look at the TurboXS stealthback exhaust. Its a 4" downpipe that tapers to 3" at the midpipe, then goes down to 2.5" so you can connect your factory axleback. You can get it catless or with a highflow cat after the downpipe.

Instead of buying a 2.5" catless downpipe, you could always gut out the cats. Or buy a used oem exhuast and gut that so you still have your original.

ILiveAgain

iTrader: (1)

How big is the exhaust outlet for the stock WRX turbo? I think a 4" DP is designed for a aftermarket turbo, but i could be wrong. Sounds like a nice option for a sleeper thou. I've read alot about gutting cats, but it would be nice if someone had a link to a write-up on gutting.

subie OCD

iTrader: (11)

4" TXS bolts up perfect with the stock turbo. Here is mine, with a comparison of the stocker --
BTW, I have the full turboback using the TurboXS standard muffler and high flow cat.

ILiveAgain

iTrader: (1)

well suck me sideways.
That’s a pretty efficient design.
Does anybody have a link for a cat gutting write up?

ILiveAgain

iTrader: (1)

Ive found alot of good info, but it would be nice if someone could link me to a write-up for gutting a cat.

Also, I would like to buy new exhaust gaskets. I was planning on purchasing them from the dealer, but if anyone has some advice on this issue, it would be welcomed.

Thanks

ILiveAgain

iTrader: (1)

bump for some advice