QUESTION : The restricted crossover pipe....

[scottyaurorav8]

So I had a chance to check out this restricted crossover pipe everyone mentions is the biggest restriction for our cars. I know its wedged between the engine and tranny. I saw that it was flat pipe on the underside of the car.
My question is would the car benefit from a cylindrical pipe smaller in diametr to atleast fit in place even if you have to remove that metal shield protector, rather than have a flat pipe?
Im sure I could have my buddy at mineke fabricate something custom, even if the pipe extends downa bit. Has anyone tried anything at all.... I bet this would also open up a more throaty engine sound too.

[ntrenn]

One design feature to remember.....the crossover pipe is double wall to minimize the heat transfer to the surrounding components. Even my OLD S10 had a double wall downpipe...

[bobsblue95]

I don't think it's as big a restriction as everyone assumes it is. The engineers couldn't have allowed a big imbalance in back pressure while still maintaining the power and smoothness we have. A "squished" pipe maybe be shorter, but it's also wider. If you calculate the cross-sectional area, I doubt there's much if any difference. At least one or two people on here have made some attempt to replace it.

[NinEFivEFourOH]

That's on my list of mods for my 95, next to the custom set of headers I've got lined up. I would honestly not worry with that and just go directly underneath the engine and trans instead of in between them... That way you can have better flow all through out the exhaust system, more consistent anyway...

I also plan on making an extra set of headers and a new revised cross over pipe to be able to make extra sets of them to sell to people. I would try to make it affordable, I'm sure you would see anywhere from 20-30 whp with these headers I've got designed. (a 2.3 quad 4 high output engine with a well made header nets 20 to the wheels... Imagine how much a northstar v8 with a much less restrictive system would benefit...

[scottyaurorav8]

Yea I was contemplating having the pipe bypass going inbetween the engine and tranny and just go underneath instead, but I think it would look terrible havinng those pipes sticking out and beingso visible.
I was thinking more along the lines of just keeping the crossover pipe ends, but round the flat portion to allow more flow and just heat wrap it to account for that double layer...which I think will allow for the pipe width to increase since it be thinner. I think this will open a lil more flow.

[bobsblue95]

Not just look terrible but surely too close to the ground. How long till it gets pancaked?
Just make sure you get some real dyno numbers before and after.