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Discussion Starter #1
I had a few questions here about my hemi swap. Mostly I'm posting this here are a help to folks that search.

I swapped a 2011 vvt hemi into my 2011 JKUR. Total cost...under $10000
heres the rough numbers:
1. found a brand new engine and trans from a grand Cherokee that fell off the car carrier(6 miles on the odometer) . It sat for 4 years but I got the engine and trans for $3200 with tax.
2. Todd at JSS sent me a hemi kit for my application. Radiator, harness, computer, motor mounts, dual battery tray, transfer case shift bracket, AC lines, $4200
3. Custom exhaust at a local shop $570
4. 2010 valve body $260
5. air cleaner, fluids, odds, ends $500

total was about $9000

It has the grand Cherokee cats, and should be CA legal.
just about 400 hp

The hardest part of this conversion is gathering the correct parts. It took me 2 months of time working on it every day to get the parts I needed.
Here's the cheapest way:
Get a 2010 hemi with the trans. From a ram. If you need it to pass smog in a 2011 on, just stick to the story... No one knows what year the engine actually is, just don't try to say a non vvt motor is a 2014. It's hard to feel bad swapping a motor that's identical in every way. I had to swap the oil pan, pick up tube, valve body, to 2010 parts. I noticed that my exhaust manifolds were a lot bigger than the ones from the 2010 down so i used them. This caused me to push the firewall in a bit to clear the passenger side exhaust. The 2010 manifolds do not but you need to buy the $340 grand cherokee manifolds.


Here's a things to think about before you buy an engine for the swap:

1. engine and trans. You have 2 options. Truck or Grand Cherokee. both have advantages and disadvantages.
The argument for the truck engine: 30 more HP, made from higher compression and a better intake. it also fits better because of the way the accessories are mounted. it cools better because it has a mechanical fan. JSS also offers a York mount for the truck motor but not for the LX style grand Cherokee motor.
The argument for the grand Cherokee engine: You can use the stock exhaust manifolds (saving $300) and the stock throttle body air cleaner junction (a $350 part for the truck motor) it runs lower compression so you can use 87 octane. The AEV kit will allow ONLY this engine.
Both engines use the same 545RFE 5 speed automatic.

2. The year of the engine.
The 2010 and down VVT grand Cherokee or commander engine has the most usable parts. You can use the intake adapter manifolds, oil pan, and everything except the transfer case adapter (Tcase adapter is $230 at the dealer and the seal is $20) This is why they say it doesn't matter if you get a 2wd or 4wd trans.. the adapter has to be changed anyway because the quadra-trac t-case has a weird 8 bolt pattern and a jeep t-case won't bolt to it. I looked at it hard to see if I could just drill new holes and there is no way.

Oil Pan
My 2011 engine had a front sump plastic oil pan that would have hit the axle on compression. I bought a truck oil pan ($80 at rock auto) the oil valley seal/pan gasket ($35 at rock auto) The oil pickup tube was from a junkyard for $20. The 2011 oil pan also had the dipstick in the pan, but the truck pan does not. the engine has a boss cast into it for the truck dipstick so I knocked it out and bought a truck dip stick.

Exhaust
The 2011 engine also has much bigger exhaust manifolds (I measured them to be about 3/4" bigger inside diameter than the 2010 manifolds) so I used them. the drivers side works great but you are going to need a great exhaust shop to get the passenger side in. My jeep has been back at the exhaust shop 4 times trying to get it all to fit. The exhaust systems from JSS are $750 and the shop gave me a full exhaust for $570 installed but I provided the cats. If I did it again I might just buy the JSS exhaust but it doesn't come with CA legal CATS. I had the legal cats so I didn't want to have to pay for cats, then cut them out and weld in different ones.
I have heard a lot of stories about folks using the stock jeep exhaust but they burn up the cats in less than a year. My stock exhaust only had 1 O2 sensor per side and the hemi uses 1 upstream of the cat and 1 in the cat on each side. the harness from hotwireauto also had 4 O2 sensor plugs so I'm glad I went that way. I'm sure when I go to get the referee to pass it I'll be happy too. The 2010 manifolds have a little more angle on the dump and fit better. I only know because I ordered the manifolds as per the BOM and I was able to measure and compare them when I had them side by side. I'm glad I used the 2011 manifolds in the end but I wouldn't swap if I started with the 2010 and down.

The rest is a few other tricks and tips:


Wiring Harness
This was the easiest part. The harness comes built for your application. I compared it to the stock 2011 grand Cherokee harness I had and it has a couple extra wires in it. The harness is beautiful, it fits perfectly, and every connection is labeled. Hotwireauto sells them for about $1100. Funny thing is I ordered it from JSS so I knew his computer would work with it but it still gets shipped right from hotwireauto. I never even called or talked to hotwireauto, the harness just fit and I couldn't be happier with it. There were 4 wires on a pig tail that were labels for C3. C3 is the connector on the gauge connector that does not come on the harness. the wires come labeled for C3 pin 5,6, 8, and 33. Thankfully I'm a retired marine avionics tech and I have a lot of experience pinning connectors. the stock plug has plastic plugs you have to pop out of the connector where the pins go, then the pins snap in. You'll need some very small tools. The whole thing took me about 20 min. to pin the connector then another hour of routing the harness correctly and plugging in all the connections.

Computer
Another one that's easier than you think. Todd at JSS sent it to me. I plugged it in and it works. I did add and extra ground to the case as a precaution. I'm anal about grounds.

Motor mounts
JSS motor mounts. There's a youtube video by Todd that shows where they go. I used a big steel blade in a sawzall to cut off the old mounts and an angle grinder with a flapper wheel to clean it up. it was a lot of work getting the old mounts off but I probably got them off and cleaned up the frame in about an hour. I was super careful with the brake lines on the drivers side that are close to the mount area but I still cut one. I replaced it. I suggest taking your inner fender liners out of the front for the duration of the swap. It really made everything a LOT easier to get to. I welded in the new mounts with my miller 210 220v welder. The mounts and frame are all pretty thick and I wouldn't want to weld them in with a 110 welder. I've been welding quite a bit with this same welder for over 10 years so this was not a concern for me to do it myself. The rear tranny mount bolts in. Try not to put the stock cross member in backwards like I did. I had to take it all apart and re do it.

Fuel line
JSS sends a fuel line adapter. very easy. it screws into AN6 connections which I like a lot and they are easy to work with. Fortunately the local hot rod shop stocks these.

AC lines
Don't be a dummy and sell your 3.8 with the short AC line attached to it like I did. It's on order ($56 at the dealer). The larger AC line from the firewall to the AC compressor is provided in the kit. the smaller one goes to the condenser and I was able to use the stock one. You have to put the lines on before the Heater hoses because the firewall port for the AC lines is really right behind the heater hoses.

Heater hoses
I cut the stock heater hoses down and used them. They only have to go about a foot and they get routed behind the engine. (like I said, right in front of the AC lines) the heater hoses and AC lines fight for space a bit so I bent the AC lines around till everything fit.

Transmission Cooling
I used the stock grand Cherokee cooling lines and ran them to a tranny cooler I bought at the local hot rod shop for $56. it came with the clamps and hoses. I did not cut the stock grand Cherokee lines. JSS sent a nifty tranny cooler mount in the kit that I used.

Engine Cooling
I ordered the radiator from JSS. I'm not sure who made it but it fit absolutely perfectly. The stock fan and shroud bolted right up. The stock fan motor sits 3/8" from the water pump pulley... it's very close.
The radiator hoses I used I will not post. I found some stuff that worked and cut them to make them fit. Todd has the correct ones that he gave me and i'll swap them out when I get a chance.
I'm a good test subject to see if there are cooling issues. I'm running very heavy 38's on a 4 door heavy pig. my engine always got hot climbing up mountains in the summer so I'm going to keep a close eye on it this summer when I'm going to my cabin in Big Bear. I did a little trick to the cooling system. I wired the out hot of the low speed fan relay to the on with the key circuit of the jeep and the high speed fan to the low speed fan circuit. The result is the low speed fan runs whenever the jeep is on, and the high speed fan runs whenever the low speed fan would have run (almost always). Not sure if it's recommended, but it's working great and it never gets hot.

Driveshafts
they are supposed to fit, but my rear driveshaft was always a bit too long. The kit moves the rear of the Tcase back 3/8" and that was too much for my nice 1350 CV shaft. I had an inch and a half cut out of it figuring it should fit if I swap in a 14 bolt some day. Front fits fine.
 

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Discussion Starter #2
have 1600 miles on it now.
First of all, it must be said that the VVT hemi makes WAY more power than the supercharged 3.8. I had a ripp stage 2 with bigger injectors, tuned PCM, headers, but the hemi is a lot different.
The hemi has learned a bit and now it lights up my 38x 14.50 toyos
I have a good comparison because I have the exact same jeep with the same tires, gears, everything except the engine and trans are the same.
I did get much better mileage with the supercharged 3.8. I was getting 15.5 mpg with the 3.8 and I'm only getting 13 with the hemi, but some of that is because its just so fun to hit the gas now.
The engine had old antifreeze in the coolant system that I thought I got out, but my heater core got clogged so it must have still had some in it. I flushed the system backwards and it cleared it out. Now it's clogged again. I'll have to take the radiator out and flush everything. That was the only problem Ive had so far.
 

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Awesome! This is dream world stuff for me, but I always love seeing V8 swap threads. My turd 3.8 pisses me off every time I drive my Jeep.
 

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Discussion Starter #5
Yes, installed in the garage.
I think I could get a used hemi in a JK correctly for about $8000 if time were not a factor and you do everything yourself. The engine, tranny, harness, computer and motor mounts are all you really need to buy. The rest can be pieced together.
 

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what state are you in if you don't mind me asking?

and how do you just find a hemi sitting for that long?
 

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Discussion Starter #9
Here's why I went with this engine...
So there I was with a supercharged 3.8 with bad head gaskets. I was about to replace the gaskets and found this engine o. Craigslist at a local junkyard for $3000 with the trans. Seemed too good to be true so I looked at it and sure enough.. They had the whole grand Cherokee there. I talked to Todd and he said over380 hp with a very mild tune.
Because I needed a. Engine, and I found a really nice hemi I went that route.
I recently swapped an ls into a fierro and I'm just amazed at how much lighter that engine is than the hemi, but I think the hemi feels stronger though my 5.13 gears in the jeep might explain that
 

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This is awesome. Thanks for sharing. A hemi swap was originally on my agenda as well but there appears to be no solution for manual transmission folks in California because a transmission swap is also required.
 

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Top thread, thanks for posting. I have one of Todds kit on the water, as we speak, so your timing is spot on. Will be interested to hear how it runs up to your cabin all loaded up.
The achilles heel of the Hemi swap seems to be cooling the big bugger when loaded up, so your review will be interesting.

Will be using this thread ( and others on JKO) as a reference when I start my swap, so thankyou.:beer::beer:
Rod.
 

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Discussion Starter #12
10000 miles

An update to the thread.
Hemi has 10000 miles on it now (in 9 months!) and it really is a joy to drive now. my wife hated the supercharger but loves the v8.

I would not use the cut stock heater hoses. I think they were pulling on the heater core when the engine torqued over causing the core to fail. I would just buy some heater hose and make new ones.
I would also use a truck engine. no reason not to.
if you are on the fence, do it.
I'll need new 38's soon
 

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Discussion Starter #14
not yet.
I have some issues with smog.
first I have to find a stock airbox that I can stuff somewhere. AEV sells a new lid for the stocker.. for $235.
Then theres the milage. apparently in CA you have to have 80k miles for the swap to be legal. jeep is currently at 72k so I need to put on another 8k before I give it a shot for the smog.
everything is there and I don't have any codes so it should pass if I can get past those last 2 obstacles.
not sure when I have to smog it.
new vehicles don't smog for 6 years but this is a 2011 and the plates are due in December of this year. If I need to smog it in Dec then I might have to get creative with the milage. if I get another year then it will have plenty.
the new smog is easy.. they plug it in and look for codes. Since I have no codes I'm confident it will pass.
 

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Discussion Starter #16
So you bought the JSS kit? If so what else did you have to piece together like you mentioned before?

Use the JK AC condenser?
I had a couple issues unique to the 2011
one of my AC lines had to be made custom but I did use the stock condenser.
my cruise doesn't work. JSS said I need a new switch but it's been over a year and I don't have it.
I think the 2010 and down swaps with a truck motor are more complete. Either way, be prepared to ask a lot of questions and simply use AEV's install instructions.
 

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Do you know roughly how much the t case moves with the JSS mounts? I am hoping to swap engine next winter but am about to swap in tons and need to order driveshafts, don't want to have wrong lengths after hemi. Thanks
 

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Discussion Starter #20
I am still running this engine. I have almost 50000 miles on the hemi now.
the best mod I've ever done to it. no problems at all except 3 electric fans. my only regret is that I wish i had used a truck engine, but this thing is pure joy to drive and off road now.
 
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