Pics of 03-04 WRX exhaust mid pipe ?

discopotato03 · Post by **discopotato03** » Sun Dec 07, 2008 4:56 pm

Hi all , if anyone has pics of the middle section of a std WRX exhaust in that era can I see them please . I need to know what they use in the way of mufflers on Rex's .

Cheers A .

Gannon · Post by **Gannon** » Sun Dec 07, 2008 5:05 pm

Wouldn't it just be easier to get an exhaust shop to make up the mid section for you?

discopotato03 · Post by **discopotato03** » Mon Dec 08, 2008 7:28 am

Hi Gannon , I don't have any Impreza middle pipes and I want to see what the factory used in the middle .

At the moment I have the STi diff back/axle back/rear muffler section and a few ideas on how to do the dump pipe .
I've been searching for WRX middle pipe section pics to see what Fuji did .

A lot of people poo hoo OEM exhausts but if you can get the right bits and rejig them to suit a slightly different platform (Impreza-L) it can be cheap and effective .

Really I just want to know what mufflers live between the dumps swivel joint and the last flange joint back near the rear diff .

If I can get the mid muffler/s and the rear half of the swivel joint cheaply all we have to do is link it all up and hang it .

I am a bit concerned because the STi muffler is HUGE and pray it will fit under the back of my RX L series .

A little OT but since you've been there , would your cat have fitted in your downpipe because that's where I'd like to put mine .

Cheers A .

Also what power output did 03 STi's have ?

discopotato03 · Post by **discopotato03** » Mon Dec 08, 2008 8:13 am

Going to the Exhaust section .

A .

BlackMale · Post by **BlackMale** » Mon Dec 08, 2008 9:59 am

discopotato03 wrote:I've been searching for WRX middle pipe section pics to see what Fuji did . A lot of people poo hoo OEM exhausts but if you can get the right bits and rejig them to suit a slightly different platform (Impreza-L) it can be cheap and effective .

Usually I would agree with the factory however in this instance I am with Gannon. Its been well documented that zorts from the factory are on the conservative side (and a little restrictive), therefore in this instance aftermarket would be relatively cost effective and save you the head ache. I would imagine the floor pans are different however good luck with your searching.

AndrewT · Post by **AndrewT** » Mon Dec 08, 2008 11:02 am

I agree that factory exhausts are more restrictive than a nice free flowing aftermarket system, however in this case I can't see an exhaust designed for an EJ20turbo restricting an EA82turbo very much, there isn't much to restrict in comparison.

However given all the dicking around you are going to face in simply getting it hung under the car, it's likely not going to be worth it.

Although it would be kindof cool to have a totally quiet car, sleeper style! Take those Hyundia Excel's by total surprise when you beat them

fredsub · Post by **fredsub** » Mon Dec 08, 2008 11:53 am

discopotato03 wrote: A little OT but since you've been there , would your cat have fitted in your downpipe because that's where I'd like to put mine . ?

You should be able to, had it done to my old ea82t wagon,
they had to do a custom bend on the bit of pipe of the cat.
But it fitted well, was a nice job with a replaced waste gate
flange down pipe part.
Probably all depends on how experienced the exhaust shop is.

discopotato03 · Post by **discopotato03** » Thu Dec 11, 2008 11:40 am

No I use a long time rally fabricator to do my exhausts , exhaust shops do "quick jobs" my people do it to a standard not a price .

As for the Rex mid pipes - no I don't intend to use them as they come , just want the flange joints and most importantly the factory swivel joint .
2nd hand factory bits are far cheaper and often better made than exhaust shop rubbish .

Making a middle pipe for an L series is very straightforward , simply link the back of the first muffler with the front of the last flange joint before the tube goes up over the NS rear axle and into the rear muffler .

From the top err front .

Cut turbo end flange from spare EA82T dump pipe .
Weld to suitable mandrel bent pipe that feeds into better cat .
Weld second bend to bottom of cat and extend to where std swivel joint is .
Use larger swivel joint from Rex/STi in place of small std one .
Weld suitable tubulator resenoator (straight through) near back of swivel joint .
Straight pipe with bend to meet last flange joint .
Rejig STi rear mufflers front pipe to suit L and hang everything off standard mounts .

Done .

Not too worried about turbo end of dump pipe because I'm not 100% sure which turbo I'll run long term .
I remember reading that the non cat exhausts dirty countries ran behind EA82T's also had a larger A/R ratio turbine housing on their VF6/7 turbos - R15 instead of R12 . The EA82 R15 housing is unobtanium but the same sized one on the early EJ VF10/VF11 is not , all it needs is EJ flanges on the up and down pipes ...

Gannon · Post by **Gannon** » Thu Dec 11, 2008 5:11 pm

discopotato03 wrote:The EA82 R15 housing is unobtanium but the same sized one on the early EJ VF10/VF11 is not , all it needs is EJ flanges on the up and down pipes ...

Even more reason to forget about the EA82T's VF4/7. By fitting EJ style flanges, you can upgrade to a different turbo later on.
The TF035, TD04, VF10 and upwards EJ turbos are a lot more plentiful than the outdated VF4/7

discopotato03 · Post by **discopotato03** » Thu Dec 11, 2008 8:07 pm

It's just that I know someone here that has a VF10 or 11 with the R15 housing on it and that housing should fit the std turbo with all its plumbing .

I don't want to get into TD04's atm because their air plumbing is different and I've got too many other things to concentrate on .

Really atm it's not a problem to use the std turbo and its std flanges , I just want the exhaust done .

Cheers A .

Gannon · Post by **Gannon** » Thu Dec 11, 2008 8:55 pm

Newer EJ turbos make it easier to fit an EJ intercooler. I assume you are going WAIC

discopotato03 · Post by **discopotato03** » Fri Dec 12, 2008 7:21 am

I have to do these things in stages because my rally people are a couple of hours away and I drive my car daily .

With a minor compromise (std turbo) the exhaust can be done in a day .

With no compromises the Spider manifold could be done in a day , remember mine will have a std TB and early TPS but the engine loom needs some customisation because they are intended for Vortexes .

The turbo and WAIC are a little more involved mainly because the later turbos are physically larger and have to sit heigher than the std one .
In std form the turbo is high in relation to the thermostat housing and I reckon thats why EA82's eat TD04's (high point steam trap and poor cooling after shut down) .
I'm going to ask my people about fabricating an aluminium spacer to raise the height of the thermostat/housing so that a turbo sitting heigher than std will still thermosyphon properly once the water pump stops .

I'm not so sure we can do the turbo WAIC etc in one day and thats not including building a header that really works .

In time .