fitting the TWE Header with VF11 Turbo and a WRX Perrin Downpipe

[Marck]

I have the TWE Header and want to swap my VF7 stock turbo for the VF11. I bought a Perrin downpipe (the best downpipe design in my opinion) because I thought WRX downpipes will fit. My problem is that the Perrin pipe hits the transmission crossmember which keeps it from bolting flushly to the turbo outlet. I tried cutting the lip of the tranny crossmember, but it still is in the way. The TWE Header moved the turbo back and up which makes it much harder to get the downpipe to install. Has anybody have had trouble trying to install an aftermarket WRX downpipe using the TWE Header?

 

I found that some had success with the megan racing downpipe, but they used their old crossover pipe w/ slight modification.

 

If I could find a 2.5 inch WRX downpipe with a bellmouth or wastegate diverter, that might allow it to fit. And I really want a small wastegate diverter like the perrin or a bellmouth design.

 

Do you think if I called TWE, maybe they will make me a 2.5 inch downpipe with a TDO4/VF11 flange and with a bellmouth or wastegate diverter?

 

Has anybody had succes with one of the aftermarket WRX downpipes and the TWE Header?

[rallyruss]

unfortunately I dont have experience with the exact set up you are trying but I did overcome a similar fitment issue with my TD04 and stock WRX down pipe. I cut and rewelded the down pipe right at the turbo flange to angle it down a little bit. its still a really close fit but has been working well for thousands of miles now.

[Marck]

unfortunately I dont have experience with the exact set up you are trying but I did overcome a similar fitment issue with my TD04 and stock WRX down pipe. I cut and rewelded the down pipe right at the turbo flange to angle it down a little bit. its still a really close fit but has been working well for thousands of miles now.

 

Exactly, the first bend (at the turbo) needs to be larger. Unfornuately, the perrin has a wastegate diverter tube which makes it harder to modify. I did consider cutting the pipe between the first and second bends (where the pipe goes down under the car) and lengthening it with more pipe, but after careful measurement I found that it still will hit the tranny crossmember. If only that first bend was larger.

 

Update:

After looking at it again, I don't see why I can't cut it at the turbo flange, angle it down, and reweld it. That actually might work. Thanks rallyrus. I don't know how to weld, but I wonder how much a welding shop will charge to do this.

 

Keep the suggestions coming.

[Subarutex]

Marck... this is what needs to be done to fix your problem. Unfortunately it involves finding someone that can weld stainless... Should be able to find someone to do this. I know several shops in the Seattle area that can do it...

 

What you need to do, is cut the straight section of pipe in the middle between the first and second bends. Before cutting mark a line on the pipe, to line it back up with. Add approx. a 1" piece where you cut, and reweld it. By doing this, it will lower the back end and allow it to pass the trans. xmember.

 

BTW... I have not done this, this is just how I would go about doing it. I have a stock wrx downpipe on my car, and just had to remove some of the heat sheilding at the bottom of it for it to clear the xmember. However, I also do not have the TWE header.

[calebz]

I also ran into the problem of the xmemeber hitting when I did my TD04 with the stock WRX DP.

 

I got a little lazy and torched right above that second bend until it was red hot and pulling it down just a hair.

 

Have since replaced it with a custom piece made to fit.

[avatar382]

For a while I ran a stock WRX downpipe with the TWE header/VF11 on a XT Turbo.

 

The downpipe was touching something down there in the chassis, so there was some vibration at times, but nothing worse than that.

 

I later had the the stock downpipe cut off at the flange and a custom downpipe (actually, exhaust) welded on.