chuck45

I spent a good number of years i the car biz and have an abiding interest in everything that burns petrol. While traveling I have rented numerous trucks and have been less than impressed when driving a Hemi powered truck. On the other hand when driving a Chevy, even with the 5.3 I was always impressed (part of that is the wonderful transmission). I also have driven some Suburbans with the 6.2 and my guess is that my JK and the Suburban weigh about the same (mine is 6100-6300 depending on gear packed) and I have been impressed with the performance.

As to the electrical nightmare I would guess it was quite challenge; but it seems that Robbie really knows the ins and outs of the JK electrical system. FWIW he owns nine repairs shops in addition to the JK conversion shop. I spent four to five hours with he and Tom going over everything and it seems he made a wise and prudent decision early on. That was to keep engine and trans management separate from the Chrysler electronics. It is common to do this with Chevy engines when putting them in other vehicles. And then he kept the accessories all Jeep. So the engine actually uses the Jeep PS pump, AC comp and alternator. It seems to be an elegant solution to the electrical problem while allowing the use of a different brand engine that happens to be lighter, smaller, that has more useable power, is easier and cheaper to repair and easier to boost he performance of.

Talking to folks about mileage leads me to think it is somewhat variable. If fuel economy is important the 5.3 is the way to go as it will get into the low 20's. What a 6.2 does depends seems to depend on tires and gear ratio. It seems that 4.10's and 35's work real well and can get high teens. The engine has the torque to do it. My initial mileage is likely to be worse because I still have the 5.13's the 3.8 demanded and I will stay with them for about a year (and go easy on the loud pedal) until I can go with 60's at which time I'll change the gearing to something more appropriate. I'm thinking 4.56 unless i go to 40's in which case I may do 4.88's.

chuck45

All I can say is when you start calling my baby ugly...I do take offense. I've spent a ton of hours, blood, busted knuckles, and sweat equity getting my JKU to its current state. forgive my pettiness, but when I hear someone call my Jeep a POS, I'm not going to bite my tongue. Again...check Ward's Top Ten engines for 2012.

I can't wait to see his build either, but the justification behind it ( if you read back through the posts ) is that any Jeep with a V-6 is garbage. I couldn't disagree more.[/QUOTE]

Well then I drove a piece of garbage for 4 1/2 years; and would still be driving it if the thing hadn't started burning oil like it was gas. And believe me, I had no intention on spending money on an engine conversion right now (in this economy) and wish I didn't have to. The fact that I think Chrysler made a lousy choice in the engine they replaced the 3.8 with isn't a slam on you or your Jeep. Like I said, I'm glad you are happy with yours; in the end that is all that matters. But my opinion, after renting one, was also my honest appraisal. I had hoped for more. The friend that was riding with us, who had been considering a new JKU Rubi, decided to stay with his LJ and put a 5.3/6L80 in it instead. But keep in mind I am dealing with 4500 ft to 13,000 feet and that really colors my opinion.

Yankee

I can see how some might percieve the Op's comments. They are opinionated towards his rig, his experience, where he wheels, and even the elevation he lives.

Personally, I do not think the 3.6 is a bad motor and it is amazing what they can get from small displacement engines nowdays. The 3.6 gives my wifes new 2012 Grand Cherokee plenty of pep. If I lived at 10,000 feet though, I would want a blower on it.

However if you look at his signature and the money (and weight) into his rig, where he lives and wheels, then a stock 3.8 or 3.6 is not an ideal replacement and a V-8 (or diesel) seems to me a logical step. He is probably wheeling with 7k of weight at elevation, why would he stick a 3.8 back in!

So he likes the LS over hemis, and makes some good points. My hemi has been problem free for over 3 years and bash it all you want, the 6.1 keeps me grinning. But I would install what he is doing in a heartbeat also. They did not have the LS/Jeep electrical crap ironed out to my comfort level in 2009 anyway.

His reasoning is much more logical than my 2 door flat land 2-tracker where I installed a V-8 just to keep a fast vehicle

Hell leave it stock or lift it 7 inches on 44's or stick a rocket engine on it (or both), just post pictures and keep waving!

project06tj

What it comes down to is:

Everything is relative.

In my situation, and 95% of others running a 3.6L, weight in not a huge issue. I don't have much added weight at all, and I live at a considerably lower elevation than the OP.

In his situation, he is up in the mountains, with a JK loaded full of people and presumably gear.


Where I'm at, and where my Jeep is at (modification wise) I don't NEED a bigger motor.

I can see why the OP would/does need a bigger more powerful motor, and I can see why he would be unhappy with a 3.6L.

That said, I completely agree with you in the sense that Jeep should have given the Wrangler a more powerful motor than what they did. However, coming from a 4.0L, they are improving.

Maybe by 2020 we can have something with some real power right off the show room floor. But I doubt it.

rays0852

I still think the JK has "real power" with 285HP. Altitude makes a big difference. I just think calling the 3.6L a POS is ridiculous.

That being said...the implication of putting a Hemi, turbo 6, or even a high-torque diesel in a JK would constitute upgrading not just the front axle in non-Rubicon models, but possibly a replacement for the D44 in the rear. IMO Chrysler may have been able to get 300+ out of the 3.6 in the Wrangler application, but looked at that D30 and cringed.

That would mean substantial increase in cost to the tune of $1,000s. One of the beautiful things about the 3.6 intro was the price was within a couple hundred bucks of the outgoing 2011.

Can you imagine paying 45-50K or even more for a Rubi and THEN having to mod it?

SergeantChuck

Subscribed to this thread. Once I blow up my engine I plan to do a LS3 swap.

The way I see it is everyone is allowed their opinion. I have a supercharged 3.8 and a 2012 with the 3.6

Although the 3.6 is stronger than the 3.8 I kind of agree with the OP. Once you modify them like we do regardless what V6 it has people are re-gearing and people are standing in line to get a Ripp SC for the 3.6

It may be stronger but in my opinion it is still not strong enough.

Flip94ta

I'm one of the 95%, no big tires, flat land and I'm at 1200ft elevation. So I think the 3.6 is great. But my LS choice would be the LS2. It had a short run in the GTO, 400hp, 400ftls and 6.0L all aluminum block.

I remember the first time I heard the L9H, I was in the grocery store parking lot and I hear this engine fire up and I'm like, holy crap that sounds good. I start looking around for a Camaro with a manga flow or corsa pipes sticking out the back and all I see is a soccer mom backing up her candy apple red Escalade.

Mean 69

Newb confession - I have a '12 3.6 and I love the damn thing, but it's stock now, although I didn't echo the comments about high altitude driving, I just got back from Ophir Pass and a few other local easy/moderate runs, unloaded, and the engine wasn't an issue for my 4 door. What WAS an issue was my scared-of-heights reaction to many of the shelf roads, but man it is beautiful in that part of the world, and I am sincerely intertested in finding a way to make a living out there and relocating from So Cal. Anybody looking for a high tech operations/engineering guy?

I am also a hot rodder, and without question, THE best engines to covert to these days, without question, are the LS engines. Incredibly well supported by aftermarket, excellent factory high performance pieces (cams, cranks, heads, blocks, everything) you can easily build one to focus on any virtue you'd like. I have a cam'd and ported head LS3 in my 69 Camaro, makes an easy 500+ HP and is completely tame on the street. Others I know have 600 N/A, 750 N/A, and well over 800 forced induction variants and ALL of them are streetable - WAY more so than the 600 HP old school BBC in my El Camino. If I was even thinking about swapping to a V8, from the extended experience base of the hot rodding hobby, there is no doubt I'd choose the LS over any HEMI. It's not a knock on Mopar fans, it's just simply that the LS engines are really that good, and that much better, period. The HEMI cylunder head chambers are neat and it's cool to say you have a HEMI, but the heads on the LS engines flat out work, and the bottom ends are both light, and strong.

IF I end up moving out of California, where such a swap wouldn't allow smog/registration, and the old bullet needs replacing, I am virtually certain that this is the direction I too will go. And again, even though my rig is stock, light, and 34" tires, and the 3.6 worked/works just fine, I can see where huge tires and lots of weight would demand a bigger round in the chamber, and knowing that this is where my own rig will migrate towards, I'll be watching this conversion closely. Best of luck, thanks for sharing.

Mark

chuck45

It is harder to make the LS2 work in a JK. They have found that the L9H or its predecessor, the L92 I think, work best. Both the L9H and LS3 have better HP and torque figures than the LS2. Also the latter models have VVT which really lets them make a ton of torque at very low RPM's and that is what makes them work so well.

You ought to hear a 6.2 in a JK with the right exhaust. I liked the way Robbie's sounded so much I'm going to have him do the exhaust for me to. My wife would like it a little quieter but I told her if I'm going to this much effort and expense it is going to sound like it too!

chuck45

Well, i hate to be the one to tempt you, but Robbie does these conversions for California customers and gets them smog certified. The conversions are so good they are California legal.

I hope your wife doesn't want to shoot me!

Chuck