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Topic Review (Newest First)
05-23-2013 09:20 PM
10Anvil Bottom line is if you are doing a swap the LS and 6L80 combo is a better product....not to mention easier to work on with lots of head and cam packages available.
05-23-2013 08:01 PM
rirrgang
Quote:
Originally Posted by 08 Ryan X View Post
Do you like it?

What was the cost?

Ho is fuel milage after?


Overall comments...
Who wouldn't like it?
more money than gas in a 3.8 for many many years.
MPG is not a factor if you can afford the transplant.....Really.
05-23-2013 11:51 AM
JKDozer Wow, excellent read !
05-23-2013 11:25 AM
jims68
ls in jeep

I have not been on here in a while and have read the conversion conversations and let me tell you once you have gone LS you won't go back Jack! Yes the putting a Chevy into a Mopar had me down and I was within a phone call from doing a Hemi but I really liked the transmission and motor combos Chevy has right now. We have several hemis at work of every years vintage, work great, sound great but every once in a while loaded or not the shift patterns just get all messed up! It is like there tables don't overlap or they are not as adaptive and unless you floor it the thing will just labor like a 3.8 does! Next deciding factor was open the hood of a truck and look at all of the space for the heat to get out. Radiator is huge but so it motor. Looked at many conversions and seen how tight things get with the Hemi and how the steering needs to be modified and such. Started to look like my Duramax and started to have flashback of my overheating problems there! From what I have heard, seen and experienced the thermal efficiency's are what get the Hemi in trouble just like my Duramax did. Stop and go traffic or rock crawling along the slow speed stuff seem to be the culprit on the Hemi conversions where the thermal displacements slowly get you in trouble. The stack or frontal area of the jeep is not great for cooling then add air conditioning, bumpers, winch, and the restrictive engine bay and you can see where this is going. Just like my Duramax some people never see this happen but the first time it does it will be at the most unpleasant of times! Now fast forward to now. I put in a 2011 all aluminum 5.3 VVT with AFM and the 6l80 6 speed auto. The motors are great but the transmission makes the package! A correctly tuned 5.3 and transmission program will wax a 5.7 and give many others a hard time. For some reason the Ecotechs like me and so far I can let off and pull them back in. The stock 5.3 tune is no slouch but there is alot to gain. Stock is just under 330 horses and the ultra low first gear and the 4.10's with 35's launch hard! About as hard as the stock stuff will take hence my decision on the 5.3 and not the 6.2 which is another 80 plus hp but needs premium gas. The overall package is smaller and not much bigger then the 3.8. It is longer and will just clear the fan. I put mine as far back as possible to clear the fire wall which leaves the radiator in the stock location. You can move it forward but then need to shim the radiator forward but can use the stock drive shafts yet if you have a lift. Mine was burnt out and the front drive shaft was shot so a Tom Woods was in order any way. You use the 241j transfer case stock on the non Rubi's and this is plenty low. In low I hit the rev limiter almost immediately so I rarely use low. I originally had 5.13 gears and this thing was just a hot rod but not a over 60 machine at all! Most have been settling in at 4.10's to 4.56's depending on use and tire size unless they are all stock yet. Robbie the owner of Motech has a stock chassis 5.3 like mine and a 6.2 lifted JK Unlimited at his shop plus usually many Hemis around also to compare to. I haven't been there yet but have gotten to know him pretty well with this conversion. I was one of the first ten or so kits he sent out so there were some bugs. Hell of a guy and his knowledge if you can keep up is so vast that it can get scary what he can do. Go drive them if you are questioning any of this or are on the fence. I also liked the fact that the two systems Mopar and LS are pretty much completely separate to each other. The Mopar Can Bus or data system can be a real Bear when something goes wrong. Personally the TIPM or you fuse box to me can be a big headache. All Mopar systems run through this box so when it has issue everything has issues. Anyone have there wipers go on for no reason? It is not sealed yet it is right there in the elements. Six layers of sub miniature PC board that turns pretty much everything on and of including the motor. It is the road cop for the whole system! ECM or you engine computer can die at any time. Common for these to go out too! The LS is a serial Can bus system so if one component dies it wont always take down the rest. Since they are separate if the Jeep side dies or has issues the LS side will keep going. Only issue is the fan is still controlled by the Jeep side so cooling will stop but at least you can get home yet. You still have full access to both systems and Jeep can hook into your OBDII port and work on that system just like it had before! Just don't let them overwrite the ECM! Only light I have on is traction control or the vehicle with the squiggly lines behind it. Since there is no motor feedback for this you are in a Limited mode or just like if you hit the Traction control button. The newer kits he has fixed this along with other things. I guess his latest stuff he is incorporating in makes it appear ALL just like stock unless you open the hood or know somehow it isn't stock all the way down to the bump shift stock shifter in the new Jeeps! Look up his UTube videos and he goes through alot of this along with testing and install videos. Don't get me wrong this is not for the faint of heart and neither is a Hemi conversion either if you do it yourself. But I did this kit for 8 to 9 grand with cruise control but the kit was cheaper then too. If you do just the basics and no bells and whistles it can still be done for that and he is working on bringing everything down in price and simpler to do. This is an incredible amount to chew on so ask questions because there are quite a few running around now. And yes he is pulling Hemi's out for LS's! Most of them have been for emissions compliance since some states and more to come REQUIRE this! The testing can be convoluted and confusing so ASK specifically about your state before doing ANY of these kits!! There are horror stories about this out there. With all of this said Mopar and Ford went together in on a 8 speed automatic transmission. MAYBE this will be better and get them into the same field as Chevy is right now. Last but not least is gas mileage. This was another reason I wanted a LS. I have talked to others with the 5.3 and average is around the 15 to 16 mark. Some are around 20 and I think with proper tuning and the AFM and VVT yes. I am PIG rich with my exhaust being black and my rear cats showing high values. I knew nothing about EFI or how a Can Bus works till this build and am in the process of learning the EFI Live tuning application to correct my programing. For some reason 11 to 12 is all I can get out of it! Doesn't matter how I drive it! Stock programing but with a used engine who knows. You are tying into the stock Jeep exhaust and are no where near exact as to what it came from. This is something all conversions can run into since these new motors are for the most part very well tuned so something different can effect the tune significantly. Could be the Camaro exhaust manifolds or stock cat back exhaust which is smaller then stock or the aftermarket muffler I have on now. Maybe my MAF sensor is not in range with the corresponding table! So no matter what a good tuner or yourself may need to get involved and Chevy tuners are abundant. If you have this issue with a Hemi good luck!! I guess it came down too the many options you have where the Hemi may lead to you relying on someone else to fix it. Not many of those out there! I need to break my thoughts up because this is going to suck to read so SORRY on the back side!!!
05-18-2013 08:38 PM
Txrdstr LIKE! LS only way to go! Don't know why everybody thinks a semi-hemi is Gods motor!
05-18-2013 01:29 PM
WatchThis!
Quote:
Originally Posted by 10Anvil View Post
SC really is the best option with what is available unless you absolutely have to have an N/A setup.
Are you saying a stock JK motor with boost is a better option then swaping in a NA V8? Yes it is way cheaper to just slap a super charger on a stock motor but that does not make it the best option for everyone.

If you are only talking about a supercharger on stock motor VS a stock 5.7 MOPAR swap then I also think the supercharger option is the best by far.

Parts are available and only a phone call away to swap in a gen IV LS and 4L80e and have all the electronics work the same as stock while using the stock Tcase.
05-18-2013 12:34 PM
10Anvil SC really is the best option with what is available unless you absolutely have to have an N/A setup.
05-18-2013 12:19 PM
Osage Orange I would be interested in a V8 JK if they could be used with a manual transmission. My LS6 would feel and sound awesome in the Jeep. A small diesel or supercharged V6 just seems more practical overall though and I could keep my manual.
05-18-2013 12:10 PM
WatchThis!
Quote:
Originally Posted by traitor08 View Post
I may be a little different on my thinking.

If you drive a mopar, keep it mopar.
Keep a chevy in a chevy.
We all have our opinions on things. When taking on a project like this I will go with what I believe is the best option. Not make a choice based on only brand name. Why do a custom build and not go with the best option? Budget allowing of courses.
05-18-2013 12:02 PM
10Anvil an LS2 can be had for a pretty good price. Even a H/C/I LS1 would make a good swap with a 6L80E.
05-18-2013 11:53 AM
caryt Better read up on the Hemi conversions...majority have cooling issues no matter what they try doing, they are heavy which throws off the balance and mpg's are poor. Integration issues etc.
NO way a hemi has more hp...actual results..not advertised

Ask yourself why the guys are pulling Hemi's out for a LS..taking a $$ bath in the process.

Blind brand loyalty is not the best way to go for mods.

But people do have a propensity for shooting themselves in the foot.
05-18-2013 08:56 AM
traitor08 I may be a little different on my thinking.

If you drive a mopar, keep it mopar.
Keep a chevy in a chevy.
05-18-2013 06:54 AM
jkjeeper06
Quote:
Originally Posted by MOPWR2U View Post
The take off parts become the property of AEV.
What about if you do it through Burnsville off road and not directly AEV. I believe they use AEV parts, but shipping engines isn't cheap
05-17-2013 08:58 PM
10Anvil Cheaper to go supercharged and you get better results. Unless you just have a thing for N/A.
05-17-2013 08:51 PM
scottmphoto
Quote:
Originally Posted by MOPWR2U View Post
The take off parts become the property of AEV.
WOW. That seems weak. Do they credit your account for the value?
05-17-2013 07:33 PM
MOPWR2U The take off parts become the property of AEV.
05-17-2013 04:14 PM
beatboy77
Quote:
Originally Posted by MOPWR2U View Post
I'm interested as well. Just ordered a JKU today that is going to be drop shipped to AEV on its way to the dealer; supposed to have a 6.4 in it by the time it gets to the dealer.
I was looking to do this same thing. What are you planning to do with the brand new unused engire which comes with your JKU?
03-06-2013 12:50 AM
pbrgdmkj The new Hemis are not far off on mpg from the LS motors and make just as much or more power.
03-06-2013 12:46 AM
2five22
Quote:
Originally Posted by caryt View Post
Trucks have much larger radaitors and more room around the engine to let the air out..plus they just don't get worked like a offroad vehicle does.
There are plenty of four wheel drive 1/2, 3/4, and one ton trucks that work hard off road. Some work far harder than a JK does.

A larger engine doesn't usually work as hard as a smaller unit does to move equivalent mass and overcome drag, but taking a larger engine and plumbing it to a radiator designed for a six cylinder engine is a likely weak point.
03-05-2013 09:52 PM
MOPWR2U I've been doing more research on this Hemi overheating claim. AEV uses a bigger radiator, but apparently still uses the stock radiator fan. Correct me if I'm wrong on this. It would explain the problem, because if you've got a bigger radiator, but are moving the same amount of air through it, you're not gaining any cooling capacity.
03-05-2013 07:41 AM
caryt Street JK may not overheat back west but we get lots hotter and have mountains.. but whats the point of having a engine that is limited to its usage..IMO if your not taking a Jeep offroad, driving in the Mountains-hills etc whats the point....get a Porsche

Trucks have much larger radaitors and more room around the engine to let the air out..plus they just don't get worked like a offroad vehicle does.

Adding a 5.3LS to a JK add's 67lbs...check out what a Hemi adds.

Before the LS swaps were available the option was a Hemi and you had to deal with the issues..now using a LS you don't plus lighter, cooler, faster and better mpg's only thing going against it is its not a Chrysler motor.
03-04-2013 10:28 AM
BenHedrick
Quote:
Originally Posted by caryt View Post
Better live in a cold area if you plan a Hemi...they have major over heating problems.

IMO Better do some research, guys are pulling Hemi conversions out and going LS.
I live in Florida and I've built and owned three HEMI JK's. A 5.7L, 6.1L and and 6.4L and I've NEVER had any overheating at all. The only limited overheating issue on a HEMI or any V8 conversion in a Wrangler that I've even heard of has been in high elevation areas when the temps are into the 90's and your working your Jeep hard. Either up hills, pulling trailers, etc. Mind you, the 3.8L could have over heating issue in this case too...

Just my two cents.

Ben
03-04-2013 09:59 AM
Numbercruncher
Quote:
Originally Posted by caryt View Post
Better live in a cold area if you plan a Hemi...they have major over heating problems.
The 5.3 LS stays cool 120* AC on and stock Jeep radiator.

The autos for Hemi's just suck the 6l80e is a far superior trans in every way.

5.3ls will kill a 5.7 and get way better mpg's 4-6.

Want more power get the 6.2
Want more get a ls7

IMO Better do some research, guys are pulling Hemi conversions out and going LS.
Do these "Hemi Issues" only relate to being transplanted in a Wrangler or do Hemi's overheat in Rams as well? I go to Ram forums quite regularly and never hear any of the above complaints about that engine in a half ton truck.

NC
03-04-2013 09:52 AM
caryt Better live in a cold area if you plan a Hemi...they have major over heating problems.
The 5.3 LS stays cool 120* AC on and stock Jeep radiator.

The autos for Hemi's just suck the 6l80e is a far superior trans in every way.

5.3ls will kill a 5.7 and get way better mpg's 4-6.

Want more power get the 6.2
Want more get a ls7

IMO Better do some research, guys are pulling Hemi conversions out and going LS.
03-03-2013 01:12 PM
jdambm
Quote:
Originally Posted by jkjeeper06 View Post
It's only a direct bolt up to a 5.7. IMO if you are going to spend that kind of money, go big or go home. 6.4 would be the only way
x2
03-03-2013 01:09 PM
RedSectorA
Quote:
Originally Posted by MOPWR2U View Post
I'm interested as well. Just ordered a JKU today that is going to be drop shipped to AEV on its way to the dealer; supposed to have a 6.4 in it by the time it gets to the dealer.

Are you either hiring or adopting at the current time?
03-03-2013 01:06 PM
MOPWR2U I've been researching this for a few years now. I've driven an LS 5.3 and 6.2, and a Hemi 5.7 and 6.4. The 5.3 LS is a great replacement engine, and has good torque, but doesn't feel like it has any more on top than a stock 3.6 does. The 5.7 Hemi vvt and 6.2 LS motors feel pretty much the same to me. They're good, but for the money, not enough. The 6.4 Hemi is in a league of its own for power, and unfortunately, for cost as well.
03-03-2013 12:29 PM
jkjeeper06
Quote:
Originally Posted by ohioviper
A stock 4.8 is not much more HP than the 3.6 the 5.3LS is 320HP a 6.2LS stock is 400HP.
The new 5.9 Hemi is 400 hp.
A 6.4 Hemi is pushing 475 hp and breathing easy.
The new Hemis are not far off on mpg from the LS motors and make just as much or more power.The other thing the new auto in the JK is a direct bolt up to the Hemi reducing cost where on the LS motors you will also need a tranny.
It's only a direct bolt up to a 5.7. IMO if you are going to spend that kind of money, go big or go home. 6.4 would be the only way
03-03-2013 12:04 PM
ohioviper A stock 4.8 is not much more HP than the 3.6 the 5.3LS is 320HP a 6.2LS stock is 400HP.
The new 5.9 Hemi is 400 hp.
A 6.4 Hemi is pushing 475 hp and breathing easy.
The new Hemis are not far off on mpg from the LS motors and make just as much or more power.The other thing the new auto in the JK is a direct bolt up to the Hemi reducing cost where on the LS motors you will also need a tranny.
03-03-2013 09:07 AM
caryt Do yourself a favor..check out Motec LS swaps....The Hemi is a pig, poor HP, fuel mpg's and hotter than heck.
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