PSD vs PSD

[Ggg]

I am just trying to gather some info. What are the main differences between an OBS model PSD engine and the SD model engines. I know the turbo and mount, injectors, Fuel filter, intake, and HPOP are different but IIRC they all will swap between the two base engines.

 

[94f450sd]

i believe that some time in 99 they started useing the PMRs(powdered metal rod)in them.wich from what ive read dont like the higher horsepower.

 

[Mike]

i believe that some time in 99 they started useing the PMRs(powdered metal rod)in them.wich from what ive read dont like the higher horsepower.

That occured in the '01 model year. Also the SD's beginning in 99 were intercooled and obviously computer programming is different on the SD's as well.

 

[Ggg]

I am aware of the PMR and intercooler. I guess what I am asking is can a OBS long block be used in a SD. What parts will work and what needs to be changed.

 

[BJS]

yep you can use either long block in either truck. There were some changes in the head castings in an attempt to minimize the noise from the engine over the years but as far as mechanical interchangeability no difference.

Oh wait I take that back on the early obs heads he intake ducts are held down w/ 8 bolts instead of 10. I belive that this change was made for the '96 model year or late in the '95 model run.

the HPOP check valve system was changed for the 01+ SD for increased oil flow providing adequate hp oil supply for the splitshot injectors. so you may need to change the pump as well as the front cover to make it all work right.


Edit: what needs to be changed: anything that hangs off the long block ie accessories & brackets.

 

[Doggy Daddy]

I guess you'd also need to plug the hole for the mechanical lift pump; not a big deal.