Down pipe for Suby conversion

[Sandeep]

I'm actually only using the stock TD04L-13T WRX turbo on my T4, but my question has to do with making a custom downpipe.

I want to use 3" tubing and a 1/2" thick steel flange but it looks like the stock downpipe was 2" dia ?

A 3" dia pipe does not look like it will fit on the flange. How did you guys handle this and what did you do about the wastegate gasses ? Bell Mouth or divorced wastegate ?

Thanks for any insight.

Sandeep

[LOAF]

Why not use a WRX down pipe, with no cat and modify it to fit.

That would at least solve your issue regarding mating to the exhaust housing on the turbo and give you a nice flow into what ever pipe you want to use.

I saw scooby powered beetle that actually ran the stock down pipe.. but can't remember the detail, since it was in German.

Just food for thougth..

Also plenty of guys ditching there stock or catless pipes..
Nasico, wrxfantics, i-club, or clubwrx are good forums to check out..

I would offer my stock downpipe, but not sure if I will need it for emmissions in a few months, running one of three.
VR
Alex

[Sandeep]

Thanks for the reply, but I should be a bit more clear in my need for a custom downpipe.

The turbo is mounted low, close to the passenger's side axle so the exhaust flange is pointing right at the rear brake caliper. From the flange, I need a 90 degree bend (3" CLR, it is really tight !) to the rear of the car to get the exhaust flowing under the passengers fender, where I can mount a muffler.

I have the 3" mandrel tubing, but the tubing diameter seems a bit large for the flange.

Hope I am making sense here.

Sandeep

[LOAF]

Hmmm that is a tough one.. and I think I follow..

I assume you have looked around, but I think that a Downpipe from a company called HKS may fit your bill.

Here are some pics from one of the members from the NASIOC board.


http://northwoodsinsulation.com/Rall...s/DSC01212.JPG
http://northwoodsinsulation.com/Rall...s/DSC01213.JPG


It will work fine though it is not as efficient as some other designs as some people say and may allow you to connect your piping directly to it.
Comes I think in 3.0 and 3.5.

It is non-belmouth design so not as efficient. People say that <400 HP should be ok..

Hope that helps..
ALex

[Steve C]

Hi

There is some photos of a custom pipe on a WRX/1303 conversion on this thread. http://forums.aussieveedubbers.com/v...7615#pid447365

Steve

[Turbo Haraune]

Hammer the 3" pipe oval. then make bigger hole in flange. Simple.

[Sandeep]

After asking the question, now it is simple !

Thanks for the help everyone ... I will squish one end of the 3" pipe in a vise until it becomes oval enough to fit inside the flange. I will then make the pipe for the wastegate from a piece of 1 1/2" mandrel tubing like in the link posted by Steve ....

SIMPLE !

Sandeep

[LOAF]

There are also other options.

Some guys run divorce waste gate down pipes like this one:
http://www.daddysscp.com/dcart4/prod...3&cat=0&page=1

The idea could be leveraged to meet your needs.

Just a thought, that came to mind after I signed off.. otherwise vise and hammer

ALex