Change the manifold or the downpipe?

[Daphur280]

So I finally got my V-band flange welded to the downpipe, and I originally told the guy to go ahead and make a considerable reduction in length before the bend because the turbo sits back pretty far on the manifold (L28ET), well... when he trimmed down the length he compensated it for the reducer to the flange, the piece I had him add, looking at it--it appeared to be the proper length to clear the firewall.

 

Boy was I wrong,

 

When I had mocked it up it was well into the firewall and would not work.

 

So I'm at a crossroad, do I:

 

A)Take it back and have him redo it, and chance messing it up

 

or

 

B)Weld up here the current T3 fland sits and scoot one up closer to the center of the manifold (I've seen this done before on the cast manifold)

 

or

 

C) scrap and sell everything (motor) and get an RB30?

 

heres a shot of the T3/T4 turbo (bagged) with downpipe banded to it

 

[cockerstar]

A

 

Sounds like a simple miscommunication, and it's an easy fix.

[dexter72]

Try having it cut after the Vband, shortened and then re-welded. SHould work fine.

[Tony D]

I don't know why there is any length of straight pipe after the diameter transition piece and the first elbow---that's where you went awry. Many times I see the v-band right on the elbow. The 'turbulent air' exiting the turbine really won't 'straighten' to any great degree before the elbow, so putting any straight pipe there for any reason other than a known downstream obstacle (which can usually be compensated for in several other planes) is not required.

 

Take out not a bit, but ALL of the straight portion after your diameter transition piece. Make sure your T/C rod clears, and has it's OEM heat shield in place, and you should be fine. I'm with post #2: this is no big deal, cut and reweld. This is why mocking up on the car is generally preferred--you generally only do it once then.

 

Tacking it still requires two trips to the welder/fab guy... But it makes changes like this MUCH easier as you are grinding off four nuggets and not cutting the whole pipe and cleaning it of a full round weldment (this is going to shorten your transition piece you have now...)

 

Good Luck.

[wigenOut-S30]

when I built my down pipe and exhaust I cut the pieces mocked everything up and then taped them together in the position I wanted them to be welded in using clear tape.

 

I would do this. I would cut what needs to be cut.. use tape and any other piping to get it mocked up on the Z.. then have it all welded up.