I finished updating my truck to the later model turbo assembly and got the 38R installed. Putting in the new manifolds was probably the hardest thing to do, at least the passenger side was. The bolts in the exhaust manifold didn't want to come out either. We had to grind them in half to get the up-pipes off and then heated the manifold and used an air chisel to pop them right out.




That BB turbo really pushes the air! And after comparing the intake manifolds, I don't know how any air ever got to the engine! Early '99 boot(left) new boot(right)



Interesting thing, I had purchased a van turbo earlier and decided to put the 1.15 housing on the 38R. I did some measuring on the exhaust wheels, the 38R housing wouldn't fit onto the van turbo, but the 1.15 did fit the 38R. I put it on initially and once I got it all put together, went out and test drove it. It would build more boost than what it used to, but exhaust temps and smoke were the same, didn't make much of a difference from the stock setup.
Once the thing cooled down I took the turbo back out and put the original 1.0 housing back on the 38R, got it all put back together and it made a considerable difference! A lot lower EGTs, much quicker and more boost, and much less smoke. I don't know what it is about the 1.15 housing, but it didn't work for me. I didn't see any exhaust leaks because of my freshly painted up-pipes and exhaust housing. I don't think I had any boost leaks because it could build more boost than before.

 

Looks good Adam. I bet that thing runs gret!

 

You have a bit of a mis-match there. The van turbo has a larger exhaust wheel than the 38r, so that's why the 38r housing doesn't fit the van turbo. And because the wheel is smaller, I think you're losing a little drive pressure since it can escape around the wheel. I would put the van turbo back together and either keep the stock 1.0 housing on the 38r or go with the correct 1.15 housing for it. My $0.02...

 

I did some measuring between the two wheels, and the 38R is actually larger in diameter towards the bearing than the van wheel, but smaller away from the bearing. I'm talking hundreths of an inch difference, so I didn't think it'd make that big of a issue, but I guess it did. The 1.0 housing is back on and working great. The only bad thing is I didn't do a nice paint job on it like I did the 1.15 housing; I used good high-temp paint and even baked it on. I guess I'll have to pull it off and paint it up as well.

 

Hundreths of an inch count. The clearance between the blades and housing is measured in thousanths.

Update you sig, lol. I can't wait for my 38R and up-pipes!