2 engines turned into one running 386 build thread.....

[Rawze]

The CPL2732 is a converted CM870 engine (old stock) into a CM871 on EPA credits via the factory before it was sold.

The CPL2733 is a true mid-tier CM871.


The head is actually exactly the same although they come up as 2 different assemblies. The valve cam, crank, and other hard parts are also the same.. however...

The CPL2732 has....
4923743 - pistons.
4954888 - Injectors.
3683658 - Injector cam.
4045032 - Turbo

The CPL2733 has...
4923747 - pistons.
4954434 - Injectors.
3684306 - Injector cam.
4045034 - Turbo

-- The turbo difference is unknown. it could simply be that one has the bigger cold-side housing on it and they are identical otherwise... or that they are actually 2 different tiers. If they are 2 different tiers then one will have a 12-point flange nut holding the cold side impeller in place, and the other will have a 6-point flange nut holding the cold side impeller in place. That is something to check, as it makes a difference in programming requirements and also overall efficiency.

-- As far as the other differences, the pistons, injectors, and injector cam are all part of a set to ensure the tighter CM871 emissions, compression ratio, fuelling quantity, injection timing standards. THEY MUST REMAIN AS A SET... even if the engine is deleted ... you cannot just slap in the injectors between one CPL to the other. The injector internal profile for each CPL matches up with the injector cam profile for proper fuelling and injection timing offsets. The pistons are a slightly different compression ratio as well. - These components must remain as a set. They are NOT interchangeable on the fly. You will get mis-matched components and it will not run as efficiently as it should, resulting in fuel mileage losses, programming mis-matches, and other longevity issues later on.

The programming used should also match whatever setup it has too + whatever truck specs required.