Snow, For your turbo, here is some of the criteria you need to use to pick one. How much CFM does your engine need at different rpms. How many pounds of air at boost
These are used to pick the compressor. Once that is picked then the exhaust side is used to help tune the turbo. The exhaust wheel and housing can be picked individually to form a combo to get desired boost at a rpm and not be too restrictive to the engine at cruise speeds or peaky when touching the throttle in normal driving. The opposite extreme is a turbo that does not produce the desired boost or is slow to boost.
You really need to get the books to study up on this before purchasing parts. Corky's and Hugh Mc(somethin) are great books on theory. There are newer books that I have bought that do not have the same valuable info they have. They are dated but so is this technology as is carburators. Advances have been made in both as we all know.
I like T4 turbo's because of more choices available for exhaust housings, wheels ect.
Keep in mind that a turbo is not something you just take apart and change wheels on and run again. It should be rebalanced and not alot of shops have the ability to do that. Some guys don't rebalance and get away with it, that is not the norm.
Turbo6 has ALOT of experience with turbos on inlines, keep that in mind.
Inliner Member 1716 65 Chevelle Wagon and 41 Hudson Pickup Information and parts www.12bolt.com