Swaps - LS3 vs Hemi

JC7

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I know I know... Jeeps aren't meant for speed, but I like to push the gas. I'm also positive I'm not the only one.

That said LS3 vs Hemi what do you guys think? :punch:

:jk:
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I've had nothing but good luck with LS engines, so that's my vote.
 
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JC7

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Good thoughts guys. I saw others talking about having to add Dana 60s when swapping. Is all that really necessar, I can't imagine the weight is that much more, but I guess I am ignorant to what it really would take.
 

MORTON

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Good thoughts guys. I saw others talking about having to add Dana 60s when swapping. Is all that really necessar, I can't imagine the weight is that much more, but I guess I am ignorant to what it really would take.
Call +1 (904) 993-5670 on Monday.

It’s a custom Jeep Shop here in JAX Florida.

Ask for Tristen. He does all the swaps and is very cool guy. He will tell you EVERYTHING you NEED to know on swaps with Jeeps. They build $130,000 dollar scramblers there from the frame up as well as motor swaps and everything else Jeep related.

Here’s my Jeep parked next to one of the shops $80k scramblers.

2EDB6124-19EC-4D29-A194-0840787A9A4C.jpeg
 

guarnibl

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I'm lucky enough to have both a Hemi swapped TJ and an LS swapped JK (I wouldn't touch a JL yet). I prefer the LS motor, but the Hemi can be a better choice of emissions are of concern in states such as California. Otherwise I would always choose the LS.

On second note and worth mentioning, don't expect to get more than 10-20% of what you spend on the conversion back on resale. And with that in mind, I have never seen a good swap done for ~$20k that didn't have some sort of issue (ESPECIALLY cooling). Kits (especially the harness capabilities) have gotten better of course, but it seems that $30k+ is where everything is perfect. YMMV.
 
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JC7

JC7

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I'm lucky enough to have both a Hemi swapped TJ and an LS swapped JK. I prefer the LS motor, but the Hemi can be a better choice of emissions are of concern in states such as California. Otherwise I would always choose the LS.

On second note and worth mentioning, don't expect to get more than 10-20% of what you spend on the conversion back on resale. And with that in mind, I have never seen a good swap done for ~$20k that didn't have some sort of issue. Kits (especially the harness capabilities) have gotten better of course, but it seems that $30k+ is where everything is perfect. YMMV.
I appreciate the insight. I definitely wouldn’t expect a return on “investment”. Did you have it done locally or did you use a big name like Bruiser? Also, did you have to axle upgrade too?

I keep hoping for RIPP to release for the JL to save some cash, but the more I read that may not even be the perfect solution.
 

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Guy at work has a LS in his JK - do it
 

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Then there is the 1/2 ton solution. Buy a half ton 4x4 pickup that comes with a v8. You can buy a lot of truck for what you’ll be investing in your rig and the swap.

Everyone I’ve known that has done a swap in a late model Jeep has some regret. It’s an expensive endeavor and you own it if it doesn’t altogether work seamlessly. As guarnibl points out, depreciation on any swap is like flushing serious money down the drain if it isn’t working when you go to sell it.

Just food for thought. Not saying folks haven’t had success in doing it. Just know what you’re getting into and make sure the shop that does it for you knows what they’re doing too.

BTW, another option for gaining HP/TQ is throwing a supercharger on top of what’s in it now since you don’t care about your warranty.

Again, not throwing shade on those who want to go this route. Just know that it isn’t a simple plug’n play swap if not done correctly.
 

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I won’t pick which is better, but will make a comment on the swap. I’ve got a JK that I swapped in the 5.7 Heim when it was new. I’ve driven it over 100,000 miles and have had only a couple of issues with it. I did it because I wanted the additional power and I got it. It was done by a custom shop and they took care of it while it was under warranty. It now has an a/c problem and the local service technicians are at a loss in tracking down the problem. The custom shop is over 500 miles away so taking it there is not a viable option. Bottom line...it’s going to be a hassle to get it fixed because of the swap.
That being said...I also have a new JL with the 3.6. That engine matched with the 8 speed auto runs as good as the 5.7 JK. No way would I swap for either the LS or the Hemi. I can get service anywhere I go and I love driving the JL.
 
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JC7

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Wise words guys. Supercharger with some good reviews would be ideal.
 

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I appreciate the insight. I definitely wouldn’t expect a return on “investment”. Did you have it done locally or did you use a big name like Bruiser? Also, did you have to axle upgrade too?

I keep hoping for RIPP to release for the JL to save some cash, but the more I read that may not even be the perfect solution.
I am just saying a lot of folks think if they build a Jeep and they spend $30k swapping a v8 into it, that they will get some of that back (i.e., $15-$20k). Not the case. Maybe $5k... it's essentially a mod, and mods going with the vehicle return 10-20% of their original spend at most. Rare exceptions of course =)

I had good experiences with RIPP prior to my JK v8 swap -- they have a great product.

I did it locally. Denton racing. 7.0 LSx w/ 2.9 Whipple. Not a simple swap by any means -- much more challenging than a typical basic LS3. You run out of room very quickly in a two door Jeep even doing a normal LS swap, but then supercharge it... things get interesting fast. @atl_xjk on instagram recently had a LSA swap done that turned out great.

I am running a Currie Dana 60 front and Currie Dana 70 rear. Running 42's. We put down ~700 whp on the dyno on pump gas. I think the sweet spot is a mild cam LS3 swap.

Also my Hemi TJ has been rock solid. No issues in the 20,000 miles I have put on it.
 
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JC7

JC7

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I am just saying a lot of folks think if they build a Jeep and they spend $30k swapping a v8 into it, that they will get some of that back (i.e., $15-$20k). Not the case. Maybe $5k... it's essentially a mod, and mods return 10-20% of their original spend at most.

I had good experiences with RIPP prior to my JK v8 swap -- they have a great product.

I did it locally. Denton racing. 7.0 LSx w/ 2.9 Whipple. Not a simple swap by any means -- much more challenging than a typical basic LS3. You run out of room very quickly in a two door Jeep even doing a normal LS swap, but then supercharge it... things get interesting fast. @atl_xjk on instagram recently had a LSA swap done that turned out great.

I am running a Currie Dana 60 front and Currie Dana 70 rear. Running 42's. We put down ~700 whp on the dyno on pump gas. I think the sweet spot is a mild cam LS3 swap.

Also my Hemi TJ has been rock solid. No issues in the 20,000 miles I have put on it.

Insanity! Now I want it. Lol
 

guarnibl

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Insanity! Now I want it. Lol
Trust me though, the gas mileage drops =) I get 6. Sweet spot is a mild cam LS3. You'll get decent fuel mileage with good power and you won't be exploding your $10,000 tranny.
 

jruss

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Both are trash swaps. Not worth the money, time and headache. Supercharger on a 3.6 produces more power than a 5.3 or a 5.7 anyway, without the redicilously specific guessy tuning or having to run two ecu’s and deal with emissions bs.
If I were building a buggy I would probably go with the 5.3 though. Not as strong or torquey as 5.7 but a ton of support and way more reliable than a Hemi. Still plenty of power when tuned right though.
 

guarnibl

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Both are trash swaps. Not worth the money, time and headache. Supercharger on a 3.6 produces more power than a 5.3 or a 5.7 anyway, without the redicilously specific guessy tuning or having to run two ecu’s and deal with emissions bs.
If I were building a buggy I would probably go with the 5.3 though. Not as strong or torquey as 5.7 but a ton of support and way more reliable than a Hemi. Still plenty of power when tuned right though.
I don't think there's evidence to say that a 3.6 or a 3.8 with a supercharger is going to be more reliable than a Hemi (what do you mean by 'reliable' ?). I think they're both pretty reliable from what I have seen (i.e., not leaving people stranded with a catastrophic engine failure). Biggest issue is overheating/cooling/AC from my own experience/people I have talked to that have swaps.

You're right about emissions -- it will be difficult to pass in certain states such as Nevada and California where referees are involved, etc. My Hemi TJ (5.7, 5 speed auto) went through the emissions process in Nevada, and it was time consuming. However, the swap was done right and it passed without problem. California is trickier (and an LS swap will never pass). Have had no issues in Arizona but that should not come as a surprise.

That said, saying that both are trash swaps is a bit of a dramatic statement (not even sure what that means, so I'm guessing). If done by a reputable shop at this point, you really should not run into any major issues, assuming you are sticking to the formula that's been repeated over and over -- including any tuning requirements. It did take quite a while though to get it right. Also, the harnesses have also had their foot print shrunk to the point where it's pretty much plug and play. Stray from that repeated formula and ALL bets are off. Also, cooling capacity is extremely important, and things like fender liners, grill modifications, winches blocking air inlet, and weight will creep up FAST.

But yes, it requires more headaches, more money, and more time! If that means it is trash, then I guess many of us prefer the trash swaps :) For ~99% of people, the supercharger option is fine. The only real benefit you get from the swap is A) it's unique and B) sound (if you like the sound of a v8), and C) a different power band that feels more responsive.

If I was building a buggy, I'd probably put in the cheapest reliable v8 I could source. Whether that be a Ford, Chevy, or Hemi. I personally don't care for the exhaust note on the Hemi engines though.
 
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