I have done a bit of research on these two. Not an expert by any means. I like the Hemi because it stays with Dodge/Chrsyler product and Hemi just sounds cool. As far as putting one in a jeep its been around longer than the LS swap so one would assume all the bugs to be worked out. The downside is its heavier, less aftermarket support and it seems to be a touch more expensive. The aluminium block LS weighs about the same as the 3.8, and some say more reliable. Either way I think having a V8 jk is badass.

 

Not voting being I'm not qualified to, not having any experience with either engine. I would put out there though that some of our work trucks are F-150s with the new ecoboost engine, and it is impressive as far as power and fuel economy, but I'm sure a swap kit would never be designed for one.

 

No question, LS's are great in street machines. It's hard to beat the torque of a truck hemi in an off road vehicle though. I'm a little biased, having a 5.7vvt for over two years now, but the kits are tried and true. There is a guy that is taking his hemi out and putting a LS in at JSS. He dropped his rig off there in June and it has yet to be completed. My hemi swap took 6 days.

Also, youll find plenty of hemis on the straight track!

 

LS,,, For all the great reasons already provided. For anyone who ever goes to Glamis and sand dune type off road spots,, ALL the high end sandrails are using LS platform engines with up to 1200 HP,,, and hauling ASS and beating the hell out of them in a very inhospitable environment. Not to mention all the Baja racers using the LS platform. Very few Hemi powered Sandrails and Baja trucks !!! But I say,, do what ever turns you on!!

 

I chose the Hemi simply because it works.
You buy a kit and a engine/tranny combo, install it and go.
No dicking around, no leaking, no failed emissions.
It simply works.
Yes, having 1 million HP is great, but lets be honest about a DD here.
It has to start, run and be reliable at all times.
And it is.

 

LS in every respect a better motor esp the 6sp trans.

Hemi:
Heavy
runs HOT
not that powerfull
MPG's suck
Trans is a POS
Integration of JK's system's poorly done and most if not all still has issues.
Its not a real Hemi..., but neither was the orginal...and the Chevy's still won more races.

 

Between the ls and a hemi I would go ls all day. Lighter more aftermarket better economy and after driving hemi powered trucks for 6 years the hemi is WAY overrated. Now give me the new coyote 5.0 or a ecoboost to put in my jeep and ill be happy. I used to be only mopar or gm but after owning a new ford for couple years they are light years ahead of the rest of the game

 

I drove two Hemi JKs (5.7 and 6.4), and two LS JKs (5.3 and 6.2), and the 6.4 Hemi was by far the most impressive of the bunch. It was the best performing vehicle I had ever driven. So I went with a 6.4 Hemi in My JK, and I have been completely satisfied with it. AEV tells me I have a full 3 year 36,000 mile warranty on the Jeep. AEV warrants their part, and Jeep warrants their part. The LS may have more aftermarket support, but the Hemi I have has more factory support. If I have a problem all I need to do is take it to the nearest Jeep dealership, instead of finding an aftermarket facility that can handle an LS transplant. At least that's the way its supposed to work, time will tell. I am very happy now though. No overheating, and no transmission problems with the six speed WA580 transmission. The Jeep drives like a dream.

 

This is by far the best argument I've ever heard and can completely agree with you. Only thing is the wa580 is a 5 speed and not a six

 

I wasn't quite sure about that when I wrote my post, LOL. Anyway, I love this Jeep. Thanks for clarifying.