Pandemic Series - Engine Swap

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Homeward_Bound

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Shorter post than the axle swap, but still a bit of information to be processed. It’s been stated several times that the 4.7 is the 3.7 with an extra pair of cylinders. And that it uses the same motor mount location.

So it should be a straightforward swap right? Get a 4.7 from a 2012 Ram and drop it in along with the engine harness and ECM. My roadblock comes from programming and mating. There was a programmer for the 2008-2010 KK, but the 2011/2012 got a different encryption. HP tuners claims compatibility, but have yet to read about anyone who has used them.

How complicated would it be to adapt the 4.7 ECM to the KK PCM. As well would the 545RFE be necessary to swap over as well since that is what was mated to the 4.7.

The transmission swap gets a bit more complicated due to the different control inputs if I’m not wrong; electronic vs oil pressure. If I were to do the swap, I would already be putting in a new transmission built by either ATS Diesel or from someone who sells remanufactured 42RLE’s.

Short List:

Get 2012 RAM PCM and send it to a programmer who would flash it the KK, if they could even do it.

Cut louvers into the hood for heat dissipation

Larger capacity radiator Clutch Fan will have to be removed Custom exhaust
 

Homeward_Bound

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I figured it's going to be too much work just to claim a V8 that not much more powerful than what is stock. A lot of the info I have come across has been for the 2002-2007 KJ and similar PCI bus models. Less computer headaches, but still an involved process.
 

Aceofspades

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For the cost of the swap , has there been anyone that did a custom cams and heads ; think performance related aka some lope


Got the idea from
This post “What year KJ do you have? If you have a mid year '03 or newer you will need major ****** work done,the 42RLE won't live behind that power.Also sorry to say you'll be needing way more than then forged pistons and rods,and new harden steel crank will be needed for the engine to last,and those are not cheap($2500+).The 3.7 is just not ment for high HP,for the money spent trying to get 400HP from a 3.7 you could swap in a 4.7 and do some light mods on that and be at your HP rating for probally less.Or if you want to get really fancy you could shoe horn a 6.1 HEMI in and get 610HP for $20,000(plug and play),but then to you would need ****** mods and rear end mods.”


In this thread
https://www.jeepkj.com/threads/bigger-cams-for-a-jeep-liberty.33037/
 

LibertyTC

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If you ask me the KJ/KK are the wrong platform for go fast goodies!

Now if you really want to scare elderly folks & kids off the street, better start looking for a 2008 +Grand Cherokee.
You might be able to find a cheap one with a blown engine..
Then the engine build choices & fun could really begin !

Hot Rod magazine featured Dave Webbers mega sleeper. Sit down & hold on tight, we got G-Force Captain!

He swapped in a 6.4L crate engine featuring drop-in forged rods and pistons to handle boost from the 2.9L Whipple supercharger.
The cam was swapped for a Comp Cams grind with 0.238/0.248 degrees of duration at 0.050 with 0.610-inch lift and the VVT locked out.
The stock ECU was tweaked by HP Tuners.
 

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