Official 3rd Gen Hemi thread

There are a couple things to consider.

T will divide them into the mechanical portions and the electronic.

Mechanically, the Truck Hemi has a different water pump housing which holds the alt & PS pump up high in the engine compartment. The car Hemi has those accessories mounted down low which causes interference w/ factory K-members and frames in an A-body. THe intake manifolds are different between the two but can be intercangable w/ some adaptation. Beyond those differences, the engines themselves are the same.


El;ectronically, the trucks factory ECM from the 03 is available as a stand alone ECM, meaning that it doesn not tie in the trans controls. The trans had its on ECM of sorts. The engine OEM ECM is not as tunable and you will be limited to a rather conservative cam, but you can run any smal bolt pattern trans with it.

The later ECM's all include trans controls which can be eliminated by use of an aftermarket tuner (Diablo) and it can also accomodate a wider range of cams.

If you are are satisfied with using w factory engine/cam comination and do not plan to get aggressive w/ the cam, the early truck ECM might be for you. If you are going to get a big cam and other mods, consider a later ECM.

I hope that sums it up for you.