Turbo crossover pipe routing question(s)

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Jun 20, 2018 | 08:12 PM

Kfxguy

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From: Louisiana

Turbo crossover pipe routing question(s)

so turbo gurus, I have a 2004 gto I’m doing a single turbo on. Has anyone run the crossover pipe around where the engine and trans meet together, in a car? And had adequate ground clearance. This question doesn’t necessarily pertain to a gto strictly but basically a car. Mine is lowered about 3/4” too. Or would it kill the spooling to run the pipe back just a tad past the trans pan and back up on the other side? It’s a 7875 on3 turbo, 5.7 engine and 2.25” pipe. Thanks for any help. One more thing, is a flex joint on the crossover necessary? Thx

Jun 20, 2018 | 09:04 PM

B18B1LS1

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From: Lawrenceville, Ga

I've seen lots of setups done that way. You'll be fine

Jun 20, 2018 | 10:15 PM

truckdoug

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IMO shorter is better. run it just in back of the converter and wrap it. make sure the gate is well after the merge and has priority flow

Jun 20, 2018 | 10:22 PM

Kfxguy

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From: Louisiana

Perfect. Thanks. What about having a flex connection? Is that necessary? That just seems like another possible failure point.

Jun 20, 2018 | 10:45 PM

truckdoug

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From: Portlandia

I have done them with and without. I prefer with. When thinwall tube heats up (and it gets white hot) it expands quite a lot. And without a joint to absorb that growth, you'll stress the weld joints and you'll get cracks.

My current preference is mild steel tubing, wrapped, and either a triple wall braided flex coupler or a single wall bellows type.

I have also switched from v-bands to marman flanges from GBE mandrel bending in Clackamas, Oregon.

Jun 21, 2018 | 05:24 AM

LS1-IROC

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Bellows or flex on the cross over pipe is a good idea. I put one in mine when I fabbed it up. The next time I had it apart and went to reassemble it, I couldn't believe how much the pipes had moved around. Without a flex in there it would have never went back together.

Jun 21, 2018 | 08:13 AM

Suncc49

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my 72 Nova has a crossover under the trans... does just fine... lots of kits do it that way for cars and trucks. Just tuck it tight so you don't bust it open