I'm jumping into a new project: Donor rig- '92 d350, 5.9 auto. Bad tranny.
project rig: '99 Chevrolet express van. I have been doing some looking and some measuring, and I am going to have to relocate the turbo. I have three options that I can see:
1) build an angle plate adapter to change the angle between the manifold and turbo inlet flange to get the turbo right up against the block.
2) remount the turbo to the underside of the vehicle and install a pump for the return oil.
3) build a custom header to replace the manifold that will relocate the turbo closer to the block.

Relocating the turbo to the underside of the vehicle seems like the best way to do it, but... from my limited knowledge on the principles of turbo operation, it seems like much of the efficiency of the turbo will be lost due to the lower egt's, can the efficiency be maintained by simply wrapping the exhaust? I know the turbo relocation is being done on gassers (Squires Turbo Systems) but is the principal of operation the same on a gas engine as a diesel?

The idea of an adapter between the manifold and turbo seems a little hokey to me, I like the idea of a stubby header better, I can build one if that is what I need. I was curious how important tubing size is? bigger is not always better, but on a turbocharged system does the oversized tubing hurt anything if it is installed pre-turbo( when backpressure is maintained by the turbo) or do I need to precisely calculate the size, and will it be different for each cylinder because of the difference in runner length?

I greatly appreciate your advice and comments on this, and will try to get some pics posted as I get into the project.

Keep in mind that the manifold on Dodges is special. The industrial/medium duty truck manifold tucks the turbo in tighter to the block.

Thanks wannadiesel, sometimes I get tunnel vision. Would this manifold work with my stock turbo?

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=290443906373&viewitem=&sspagename=STRK%3AMEWAX%3AIT

or could someone point me to a web site to find the manifold I need. Thanks

It won't fit your head, that's for a CR engine.

Check heavy truck/school bus graveyards or Cummins.

I've got a 5.9 non-IC from a Bluebird and the exhaust outlet on the manifold sticks straight up, and I think it might be reversible too (to tuck the turbo down and under).

I think the member with the late 70's crewcab ford that was in diesel power has a tractor exhaust manifold that sticks the turbo straight down. His is a manual so it doesnt hit the tranny cooler on the side of the block though. Im sure he will chime in. Dont quote me on that though

Straight up/straight down is the same manifold. ;)

I believe that would be this one:

http://cgi.ebay.com/ebaymotors/Cummins-B-QSB-Series-Used-Exhaust-Manifold-3906660-_W0QQcmdZViewItemQQhashZitem2a020a3886QQitemZ18042 2850694QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccesso ries

Does anyone happen to have the dimensions from the ports on the head to the outside edge of the turbo flange, Or how close the turbo will actually be to the block?
thanks guys.