realistically any upgrade to the stock exhaust system should benefit the car. Just don't get something cheap off ebay that'll burn itself up...if your not going with the Cobb downpipe i've seen some pretty cheap nvidia exhaust dp's which the second or 3rd best brand i'd choose over Cobb...

If I was you I would just save up and buy a new or used turbo back full system. I HAVE seen them go for 500-600 which is not impossible to find.
~Erakem

 

turbobacks are better than catbacks?

 

Hmmm thanks I will probably do that then. Just out of curiosity do you think the Up-Pipe would increase the boxer rumble noise or no? Oh and would and un resonated midpipe by P&L motorsprts be worth it for a 100 bucks? Say I get bot and install for only 140, would that be equivelant to a CBE system, sound wise I mean?

 

I never said that.

You probably wont see much noise difference. Just depends on the muffler honestly, I have the stock Dual tip with a Cobb Up pipe and it sounds exactly the same...

What I was saying was regardless of whatever aftermarket piece you add too it, it will make it run that much better.. besides I've heard some pretty nasty stories of not replacing your up pipe on the WRX's....

Say goodbye to pitting and broken turbine fans with a nice Up Pipe....

 

oh no i was just wondering, im still learning about all this stuff and dont really know the difference between turboback and catback

 

oh no i was just wondering, im still learning about all this stuff and dont really know the difference between turboback and catback

Turboback is the entire exhaust post-turbo, while a catback is the exhaust post-catalytic converters

Explained a little better?

 

catalytic converters are the uppipe/downpipe? meaning turbobacks dont need those? or am i way off? sorry if that sounds dumb :redface:

 

quick uppipe question, does the 08 legacy spec b have a catted uppipe?

 

The UP on our model year is basically more of a preventative maintenance item. It won't really net you any power gains but it will delete the CAT that sits RIGHT before the turbo. There has been incidents where the pre-turbo cat has come apart and disintegrated into the turbo destroying it.

If anything, install a catless UP for the piece of mind knowing that you don't have a ticking time-bomb waiting to annihilate your turbo.

EDIT: You can also just take your stock UP, gut the cat out of it, and replace, or find a used STI UP on the cheap.

 

if you can get a TurboXS model for 40 bucks, do it. It isnt hardly worth the time to gut your stocker, and plus, that is what a gutted stocker will run you if you bought it.

The uppipe will not change the tone of the exhaust, but it will bring out the noise of the turbo spooling a good bit. Throttle response will be better, as well the turbo spooling earlier. But above all that, it gets rid of the catalytic converter before the turbo. So, buy it.

 

if you already have a gutted turbo xs up pipe, it would be pointless to buy another. The main reason people get an aftermarket up pipe is primarily to get rid of the cat-but you already go that part out of the way. Swapping a catless up pipe for another catless would net you like less than 5 hp.

Btw the order of exhaust flow on our cars is:
Header, Uppipe, Turbo, Downpipe(Cat), And Catback(which includes the mid pipe and the rest)

it's the same for just about every turbo car

 

if you already have a gutted turbo xs up pipe, it would be pointless to buy another. The main reason people get an aftermarket up pipe is primarily to get rid of the cat-but you already go that part out of the way. Swapping a catless up pipe for another catless would net you like less than 5 hp.

nowhere did he say he already had a catless UP.

 

but with aftermarket uppipe and downpipes is more than a noise maker(lol) no?

Catalytic converters are very restrictive to airflow. You need to increase airflow in order to make power. If you replace your OEM catted pieces with aftermarket catless ones, you achieve this.

 

ah i see, thanks for the info

 

a downpipe also decreases turbo spool time and gives you less backpressure past the turbo. with just a catback, it would be like fatal said-just a noisemaker, since the most restrictive part of the exhaust is still right at the downpipe.

 

Bottom line: get rid of that cat in your uppipe.

 

just make sure you do it all at once,meaning the turboback and up pipe upgrade and a tune. i didnt do the up pipe so now i would have to get it re tuned :unhappy:

 

Thanks for the input guys...
Ive decided to just buy a set of OBX Headers that have an attatched caless uppipe. I found a great deal through a friend for only $150 and their brand new. I will be installing them soon and will let you know the results...I will try and get some pics up as well.

 

Don't. Those headers will break. They are gonna be a hell of a lot of trouble.

 

Don't bother with and aftermarket header. Almost all of them break on a consistent basis (some more often than others, IE knock offs like GT Spec are among the worst). The stock pieces are of the best construction quality.

 

Trust me hes right.

Just because they are powder coated in shinny doesn't make them invincible.

Usually the cheaper the product the ****tier the metal...and welds...Besides the heads shouldn't really be touched with unless you honestly plan to be putting out over 350-400 to the wheels in a Subaru.

If you are I would just say wrap the stock headers and go call it good..

 

so you're saying is BEST to leave the headers stock? theres something new i learn u guys are great, i woulda bought headers soon after the exhaust system..and probably regret it had u guys not said anything

 

on the whole header thing trust them they will crack. also i dont know why people like them they change the deep agressive sound that the wrx brings. And on the whole up pipe thing you will notice a slight increase in spool and a little hp gain. And it is good for your car you dont want your stock up pipe' cat to break apart and ruin ur turbo

 

so you're saying is BEST to leave the headers stock? theres something new i learn u guys are great, i woulda bought headers soon after the exhaust system..and probably regret it had u guys not said anything

If anything, do a port & polish job on them

 

Yes the UP is worth it. It will affect the sound, you will hear the turbo better etc.

To clear up a bunch of stuff -

There are two cats after the turbo (not one). They are both replaced by an aftermarket DP. The DP allows you to run a stage II tune (significant gains for all). The DP is therefore much more important than the catback.

You do not need to go catless, a high flow cat in the DP will be ostensibly just as good and will help with emissions.

They were saying that the stock headers are the best construction - you can get them ported and polished (& coated) though for a significant improvement.

You will need a tune or an upgraded map to safely run a DP, and to see good gains from the other parts.

 

You will need a tune or an upgraded map to safely run a DP, and to see good gains from the other parts.

he has an 02. he does not need EM to safely run a DP. However, to get the most out of a TBE/UP, a tune is a must. But not a must for safety reasons unless it's on an 04+.

 

is stock headers safe to run in an 07wrx if i'm planning to run a catted uppipe with a catted downpipe? does my uppipe need to be catted if my downpipe is? after reading about headers i really don't want to buy any.

 

Your 07 WRX doesnt even have a catted UP why in the world would you add one?

 

it doesn't have one? wow. i thought it was unsafe to run with a catted uppipe.

 

It is if you have a catless downpipe and higher boost levels.

pieces of the cat could destroy your turbo with increased EGT

 

Do not mean to hijack the thread but I just got a 06 sti up pipe for my 05 wrx, it said in the unabombers manifesto that all years are interchangeable.

I guess my question is did Subaru just change up the headers a little for the 2.5l and keep the up pipe the same?

In addition, for any one who did the swap, was there any tweaking to the up needed?

 

There sure is a lot going on in this thread.



The the 06 STI uppipe will fit your 05 wrx with no modifications.

The uppipes for 02-07 WRX and 04-09 STI are all interchangeable.

 

Thank you for the answer. Now on the engine management side of things, I have a cat back on my car already and would like to put on the up pipe as well. I read the EM section that said I should be good with just a cb or just an up, but what about both. I know the Ecu on the 05/04s are not as forgiving as the 02/03s.

Can I run both the cb and up with out doing damage to the engine of my car with no tune?

 

You're fine. But you'll need a tune when you get a downpipe.