Parts to change OBS 7.3 to SD?

Jake P · Nov 25, 2011

I have an OBS 7.3 that i am putting in an 02 SD to replace the blown PMR engine that was in it. My question is exactly what do i need to change to make it a completely 02 engine? Obviously the accessories and brackets, turbo, pedestal, injectors, HPOP, HPO res, UVCH, wire harness and plenums. What else? Front cover? Water pump? Exhaust manifolds? If someone could, give me a list of every part that is different between OBS and SD 7.3s. I'm already changing out the flex plate for a flywheel since the engine came out of an auto truck and its goin in a zf6 SD.

Biggreen96 · Nov 25, 2011

i believe the passenger side manifold needs to be changed as the obs is different. And i believe the hpop res needs to be changed depending on year of motor, due to drainback on the hpop .

Jake P · Nov 25, 2011

So the driver side manifold is the same? If i'm swapping one of them though id probably just do both since i have everything in my garage.

Chvyrkr · Nov 25, 2011

No Jake, the passenger side manifold can stay, it's the drivers side manifold and up-pipe that's a little different. I think you can even reuse the pass up-pipe...

I'd leave the pass side alone in either case, since it's already been goin through heat cycles on that head.

And the front covers are different, 02 had the integrated HPOP res filter, OBS's did not. I think you're all over it other than that. And the fuel system. Be a perfect time to build a regulated return though, get some practice for the next engine.

What year is the engine you're using? I think the front of the block was unchained after 95 (?) when they added a check ball/valve to help with drainback.

Jake P · Nov 25, 2011

Its a 95 engine. I'd consider doing a RR but i just wanna get the truck on the road. I might be selling it so the less $ i put into it the more i profit.