Motor swap ideas

Jesmatth

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Mar 9, 2020
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Georgia
I see alot of people swapping out the 2.5 with v8s but has anyone swapped the 4.0 with a 5.2. I have an 03 tj 4.0 with standard shift and a 97 Zj with a 5.2 with auto. How bad of a job would it be to swap it over.. I know the mounts would need to be swapped anything else though?
 
I'm not an expert but the computers don't appear to be compatible which I believe would require at a minimum an aftermarket gauge cluster. The ZJ is CCD bus, while the TJ is PCI. The year of your jeep makes it an excellent hemi swap candidate. I'd consider going this route. DISCLAIMER: I've only considered and researched a TJ motor swap, I haven't done one.....
EDIT: you may not need a cluster swap, but you will probably need to run the original tj computer with the ZJ computer. The correct year hemi I believe could be swapped in using only one computer.
 
I'm admittedly biased toward the hemi but this is a great, and almost surely cheaper alternative!
Having owning a C6 Z06 with a Lingenfelter built LS7, all I can say is that engine was absolutely epic. Hard to believe, but even more of a riot than my Hellcat 😮
 
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Having owning a C6 Z06 with a Lingenfelter built LS7, all I can say is that engine was absolutely epic. Hard to believe, but even more of a riot than my Hellcat 😮
Yeah, no doubt its sick and almost certainly the better choice for powerplants, I just like they idea of a chrysler motor in a chrysler vehicle, and I like the idea of a single computer doing all the talking. That, and I'm a bit of a mopar guy, but when I think Hemi, I usually think 426, not 5.7, but its still pretty cool.
 
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Yeah, no doubt its sick and almost certainly the better choice for powerplants, I just like they idea of a chrysler motor in a chrysler vehicle, and I like the idea of a single computer doing all the talking. That, and I'm a bit of a mopar guy, but when I think Hemi, I usually think 426, not 5.7, but its still pretty cool.

Oh yeah, if I had a modern Hemi, I would have to have the 6.4, but I don’t think that’s fitting in a TJ easily 🤣
 
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I'm a fan of whatever works. The LS series motors are very proven as V8 swaps for TJs and have been done successfully many times. The Hemi swap isn't as common but has also been done successfully. The motor you want to swap into an 03 wrangler, would likely be easier into a pre 2001 TJ due to computer configuration. Can it be done? Of course. If it were me, I'd be looking for a 5.7 hemi donor truck. but again, I'm a bit biased toward mopar. I almost went this route, but the truck I lucked into very cheaply had a very "stuck" hemi making it not worth the effort or cost.
Good luck whatever you decide. Should you go with what you have, take some pics and document what you run into. It will almost certainly help someone else out.
 
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The only reason I was thinking the 5.2 is because I bought the donor very cheap when my axle perches went out on me.. I guess I could sell the jeep and wait on a newer hemi
 
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The only reason I was thinking the 5.2 is because I bought the donor very cheap when my axle perches went out on me.. I guess I could sell the jeep and wait on a newer hemi
Yeah, the other thing is I'm not sure I'd bother swapping out a 4.0 for a 5.2. If you're not in a hurry dig into the threads around here and elsewhere on hemi, LS, and 5.9 swaps. 5.9 should be the same swap as the 5.2 as long as its CCD bus as your 5.2 is (96-01).
 
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I‘m partial to the Hemi myself. The Gen3 5.7 out of a Ram is a fairly straight forward swap. Chris is right, the 6.4 is possible, but because of the layout of the accessories it requires a bunch of frame modification. Mine is stroked to 392 (6.4 liters) with a complete forged rotating assembly, and makes wicked power.

But the real reason I went with the Hemi over the LS is that I hate spark plug wires...
 
View attachment 196732I‘m partial to the Hemi myself. The Gen3 5.7 out of a Ram is a fairly straight forward swap. Chris is right, the 6.4 is possible, but because of the layout of the accessories it requires a bunch of frame modification. Mine is stroked to 392 (6.4 liters) with a complete forged rotating assembly, and makes wicked power.

But the real reason I went with the Hemi over the LS is that I hate spark plug wires...
392 Hemi, I love the sound of that! Nostalgic and modern at the same time!
 
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Just went through this in another thread.

I'm assuming you're keeping your manual tranny....

#1 small block Chrysler's...not all received a pilot bushing hole. Or better yet a bore large enough to accept a pilot bushing. Whatever you want to call it.

Obviously all Small Chrysler in front of a manual got a crank bore to accommodate a pilot bushing but not all of the automatics did. There is no vin# nor engine build code to know this answer. You must literally look at it.

If your zj 318 doesn't have it you'll have to yank the crank and get a machine shop to do it or attempt to do it yourself.

You need to deal with skim.
The computers won't match up.
Motor mounts

It's not very simple but not excruciatingly hard

Good luck
 
There have been a few 5.2 swaps. Wiring harness and PCM swap ease as well as keeping it in the family. I am personally collecting parts and info on the 5.2 swap for mine, when the stock 4.0 craps out. I will rebuild it, but it is not going to get better. I like the idea of the V8 not being much heavier than the 4.0 and having 40%-50% more torque down low. My cruising speed also matches the rpm range at high torque if I went the 5.2 route(nothing a regear would not fix anyways) and the 5.2 are plenty.

Work on the plenum issues, get the plate to fix the vacuum leaks, while reworking the vanes inside for a little more low end torque and flatter curve, van block hugger manifolds ceramic coated on the inside to keep the heat where it needs to be. Stock Van cam, or something close to that and port match what you can.

May even get the AC lines installed to have AC in the Jeep and enjoy the extra torque.

Keep the year of the motor in mind as most states allow a lateral swap(same year or newer) - but not older motors.