Hi. I'm building a turbo 340 Duster. I've been looking at the pics of builds on the forum.
My goal is to keep the alternator and power steering in the stock locations. I want to run the crossover pipe under the transmission with the left feeding the right. I want to weld the turbo flange to the right side manifold, then plumb the intercooler tubing forward. My theory is that is should work just fine. Its not how most people on this site are doing it. Most are running the crossover in front of the engine.

Who has done this? What are the cons?

Jessie Buhr

 

I did this cross-over-under-the-trans thing back in 2006 on my E-body. Unconventional to say the least. I have changed everything since then but you can still see pics of that setup in one of my old build threads: https://www.theturboforums.com/threads/305400-5-inch-downpipe-pics?highlight=5-inch downpipe I was running a GT47-88 on 500 c.i. at the time and it made about 840 rwhp on 10 psi. That combo was a blast to street drive with manual trans, until I tried to launch on slicks at the track and snapped the trans like a twig.

The cons:
A) Not so easy to change plugs on the passenger side
B) Heats up the trans (not such a biggy for me since I had a manual trans at the time, but I wouldn't try this with an auto)
C) More turbo lag due to longer crossover (not so bad for me since I had 500 c.i. and smallish turbine)

 

I currently have the lightning set up with the crossover in the rear, the mustang with the crossover in the front. The engine temp on the mustang is a little higher, and the trans temp on the lightning is not an issue. If you keep the crossover in the bell housing area it will not be an issue even with an auto, if you are worried about heat with the trans and a rear crossover just use a heat shield. As far as spool is concerned just keep the crossover and all hot side piping as short as possible.

 

Gen1SVE - on your Lightning, do you have one manifold feeding the other? I did a crude drawing to help explain my thoughts. What do you think?

#ad

 

You are forcing the air against the passenger back two cylinders. Will it work? Yes, will it be efficient, I dont think so in my opinion...

 

On the lightning I have both headers are facing rearward, the right side joins the left shortly after the left collector then one 2.5" pipe goes up to the turbo. They are shortie headers.

 

X2. Try to merge them into a y, then go to the Turbo.

 

^^^Ya! Like this. Lol

 

There are a few here that have made a lot of hp with a 2 1/2 log manifold, with a rear crossover. Search for a user by the name of Quik, and log manifolds, there are a few threads on the subject. I believe Quik made 700+ rwhp with a 4.8 with a log, and figured it would support close to 1k. Feeding the stock manifold will be the problem.... but a log works well. I also used this on a 5.0 with a s465 t6 1.10 (albeit a mild build, but it spooled and worked great).

 

Here is a link to Quiks camaro build where he talks about the 4.8 in his silverado that made 700+, and builds another log for the camaro. https://www.theturboforums.com/thre...bo-project/page2?highlight=power log manifold

 

Also kb racing made a nice setup. I couldn't find it on ttf but google kb racing turbo and you'll find his stuff

 

I believe Quik was running a kb racing log on his silverado.

 

Well, after being at Car Craft this weekend, I've decided to build the Duster with a rear crossover, with the left side directly feeding the right side manifold. I decided this after refamiliarizing myself with the 3.8 turbo GM motors. They produce a lot of prove power with the same set up. I'll be sure to take photos and document the build and results.

 

I've done the same for both of my Dakotas.
I have the crossover crossing beneath the bellhousing/torque convertor area. I am running a header on one side and a custom built manifold on the other.

From the back looking forward.
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From the front looking backward.
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I ran the crossover pipe to join the log manifold at the point directly below the turbo flange so they would both feed the turbo equally.

 

Car craft last weekend..... you must be from up here.

 

Yep - I live in Brooklyn Park and work in Eden Prairie. I'd like to see your project, MNlx. Where do you live? I'll be in the Mora/Hinckley area this weekend.

 

I live in North Branch. I dont have much to see right now.... I sold my running turbo stuff. I have three current projects, a low buck 99 silverado, a 64 Rambler American, and a 51 chev business coupe for a long term project. I will be working on the silverado this weekend, and will be building a log like the one Quik was running. It would be good to meet a local fellow turbo guy.

 

I've got log manifolds on a BB Mopar feeding the turbo in front of the engine. Both sides meet in the turbo flange in a narrow Y. Logs first go forward, then slightly down and then turn up to the flange. Turbo is little over and in front of the water pump. The turbo is slightly on the small side and it wakes up in an instant. 18psi of boost and yes, it does heat up the engine somewhat but has not created problems even during the hottest days. I run CSI electric water pump with reversed water circulation.