What is the displacement of the diesels in these? Anybody know what type of turbo they use?

Depends on the year and which engine you want.

4BD1- 3.9L, indirect injection, non-turbo, 2-valve head, 88hp@2800 181lb/ft@1600, redline 3080rpm.


4BD1T- 3.9L, indirect injection, turbo, 2-valve head, 116hp@3000rpm, 232lb/ft@1800rpm, redline 3080rpm, Garrett TB2568 turbo.


4HE1T- 4.75L, direct injection, turbo, intercooled, 2-valve head, 167hp@2300rpm, 427lb/ft@1500rpm, redline 3450rpm Garrett TB28 turbo.
[attachment=0]<!-- ia0 -->4HE1T.jpg<!-- ia0 -->[/attachment]

4HK1-TC- 5.2L, direct injection, turbo, intercooled, 4-valve head, 205hp@2400rpm, 441lb/ft@1850rpm, VNT turbo (I don't know exactly what model)

Without performing any calculations, but just looking at the engine displacement and Power and redline RPMs it looks like the turbos from these engines would be worth looking into for use on a 617. What kind of boost pressure do these engines run? Do you know what turbo flanges they used?

Any idea of the boost pressures these engines run ForcedInduction?

The 99-00 NPRs I worked with had the 4HE1T but I never got to measure their boost. I know the turbo is smaller than a T3 and it screams at full power so they couldn't have had much room left for additional airflow. The Not2Fast calculator puts the 4HE1T at around 400cfm @ 3400rpm @ 14psi which puts a T3-45 at it's choke line.

my NPR van runs the same T3 thats in my 300d

for the npr the 6 cylinder larger truck uses a td7-9 mitsubishi turbo supposed to be rated as 25g i have one i was thinking of using on my 300D they supposed to make a good turbo

BJ

The 4BD1T used first an IHI RHB6, then T25 variants. The 4BD2T used the T25 variants.
The early non-wastegated turbos have a T3 flange but a large and thin turbine and a T25 60 trim compressor wheel with a 0.48 A/R housing. The exhaust housing is large (0.89 A/R).
The later turbos were wastegated and still run a T3 flange but have a smaller 0.67 A/R turbine housing and longer turbine wheel.

Factory boost 12-15psi, intercooled on the 4BD2T's. The turbo cold side is identical functionally to the T25 used on nissans CA18DET engines.

The 4H series run T28 turbos.