Hi, I live in the UK and own two 2002 4.7 l Rams. One of them has a damaged engine and I need to replace it, the only engine I can find over here is an high ouput version. Is this transplantable, I know there is some mis match but need more details before I buy the replacement engine. The VIN on the truck is 1D7HU18N02J197364 if that is any help. Thanks

 

I know there is a PCM upgrade for Jeep Grand Cherokees available when going from the standard 4.7 to the 4.7HO, but since the HO is not a true Ram engine I doubt you'll be so lucky which also means you won't find a donor PCM either.

I would say it's do-able BUT you're gonna have to have a custom tune written.

For more info on the HO and how it differs from the standard 4.7, this is an excellent site:

http://wjjeeps.com/ho_engine.htm

 

I think the biggest hurdle you'll have is if the reluctor wheel on the crank has a different tooth count. You could probably get away with loading a Superchips tune to run it (but custom would definitely be better).

 

I disagree, the HO has different cams, oversized injectors and a host of different internals from a standard 4.7. I think the PCM from a standard 4.7 would be a soup sandwich unless it was custom tuned for the HO...

 

All this is true, it's a better 4.7 than the Ram ever got until 2008. What are you disagreeing with, the Superchips part? As long as the PCM can read the sensors and a program (custom being the best way to go) can operate everything, it seems to me that the hardest part of this would be if the tone ring is different and adapting to different sensor locations.

 

Yeah, I don't think just an SC is gonna cut it. I know for a fact the guys with 4.7s in Grand Cherokees who lose the engine (usually via an overheat/head deal) and go to the 4.7 HO need the PCM if the engine comes from a donor Jeep and the wiring harness. Nobody has even been able to get it to fire without the right tune, I'm told (by a pretty well known Mopar performance shop guru) that the dual knock sensors is why the stock PCM won't even let it fire unless you have the harness that hooks 'em up.

I've been in on a couple of those swaps, pretty much as a helper...

 

Who'd of thought an extra knock sensor would throw such a curve ball within the same family of engines.