What do you use for exhuast manifolds on a 96+ dohc turbo?

[donk_316]

I know on the early dohcs 91-95 you can use 2 front manifolds and a custom cross over. this cant be done with the 96+ engine... so... what do you use?

[Aaron]

I know on the early dohcs 91-95 you can use 2 front manifolds and a custom cross over. this cant be done with the 96+ engine... so... what do you use?

A) Build headers
B) Cut the manifold from the flange on the front piece, flip the flange upside down, weld it back on.
C) Swap on 91-95 heads (<Better flowing heads on the intake side, larger volume combustion chambers for lower compression)
D) Leave the stock manifolds on, block off the downpipe exit or place an external boost controller on the downpipe hole. Then just build a custom crossover, os adjust the factory piece and add a turbo flange. A company does this setup for their turbo L36 and L67 setups.

[The Dark Side of Will]

an external boost controller on the downpipe hole.

Wastegate?

[Aaron]

an external boost controller on the downpipe hole.

Wastegate?

That's the word I was looking for, it escaped my mind at the moment, so I figured external boost controller worked :thumbleft:

[p8ntman442]

:knob:

[Aaron]

:knob:

Does External boost controller not accurately describe an external wastegate? I coulda said the thing that is outside of the spinny thing that checks how much air you have.

[p8ntman442]

hmm does your engine have boost on the outside? no, so no external boost.
Does a wastgate raise boost, and lower it? no so it does not control it.

pressure relief valve may have been ok.

:knob:

[Aaron]

hmm does your engine have boost on the outside? no, so no external boost.
Does a wastgate raise boost, and lower it? no so it does not control it.

Then what is an external wastegate? A wastegate mounted outside of the turbocharger. My external boost controller is mounted outside of the turbo.

A wastegate controls how much boost a turbocharger can make.

[p8ntman442]

is that what a wastegate does???

:knob:

[Aaron]

is that what a wastegate does???

:knob:

Well you asked if it rasies boost or lowers it. It can do both when used properly.

[crzyone]

Ok, we knew what aaron ment. Back on topic.

I looked at your rear manifold Donk, we can just block off the stock outlet and go back to the turbo through the crossover port.. Not a big deal, probibly won't flow great but it will be fine for the power levels you are looking for.

[Kohburn]

Ok, we knew what aaron ment. Back on topic.

I looked at your rear manifold Donk, we can just block off the stock outlet and go back to the turbo through the crossover port.. Not a big deal, probibly won't flow great but it will be fine for the power levels you are looking for.

the turbo kit for the NA 3800's does this - actually they mount the external wastegate to the stock outlet flange - then the turbo goes in a new crossover.. they seem to get good results out of it

[XzotikGT]

I mounted my torbo right where the rear manifold dumps into the exhaust. I was told it tould be ok there since both banks feed into it there. It has been running since Saturday, and it works fine. Actually it is a lot simpler this way, but you have to get rid of the trunk.

[Shaun41178(2)]

Hey Welcome Xzotick. good to see you here. :thumbleft: Many people here have engine swaps of some kind or another.

Feel free to share your setup. enjoy your stay.

[donk_316]

Thanks dude but i think i might be shutting that closed and riggin something up on the crossover.

I dont want to cut my truck either.

[Aaron]

Thanks dude but i think i might be shutting that closed and riggin something up on the crossover.

I dont want to cut my truck either.

That will work, but it will block flow and hurt horsepower. So for the initial stage it'd work fine, but eventually you may want to make shorty headers or something.

[Blue Shift]

I was going to go Fiero style on my swap, but I've decided to go with a super short exhaust system that bolts onto the stock DOHC setup. In that case, 91-95 or 96+ wouldn't matter, which is something I'm keeping in mind for later. It's going to be a tighter fit than... well you know, but it'll be cool if I can pull it off.

Basically, I'm going with a 1/4 donut from the exhaust manifold, straight over toward the passenger side through a short cat, 1/2 donut U bend down into inlet on a Flowmaster 80 (just to piss Aaron off, and cuz I have reason to believe it's the sound I'm looking for). Inlet on the muffler is at the top passenger side position, outlets are at the bottom. I'm hoping to shoehorn this shit in there without having to cut my trunk, which is one of my design criteria. Steven and I mocked it up by holding all the parts where they'll end up and it looks like there's just enough room to make it happen, provided everything can be connected up and supported alright. Might need some glass tape on the U bend after the cat, and some heat shielding on the passenger rear cradle mount. It'd give the option of a traditional muffler while using all stock DOHC exhaust shit so you don't have to fab stuff (unless you're using a non Getrag tranny, where you'll need to get creative).

[donk_316]

Blushift ...whats "fierostyle"....can you try to give me a better idea as to what your talking about? Im trying to visualize what you mean.

Where do you fit a turbo into all that?

[Kohburn]

fiero style = running the exhaust around the front of the engine like the stock fiero does

I chose not to do that so I could fit in a nice intercooler where the cat was

[donk_316]

I think i have seen pics of your intercooler....or was it fierox... you got pics now? your is mounted to the cradle right? infront of the engine?