palehorse

Chrysler does offer a v8 option -- it's just ridiculously overpriced.

You can order the entire HEMI ENGINE SWAP directly from your dealership (via MOPAR). It's roughly $15k for the 5.7L, and $18k for the 6.4L -- and that's just for parts!

And what do you mean that your buddy's jeep with the higher gears (3.21) is "faster"? In what way?

TheOneJeep

After researching bolt-on power options short of a SC; the number one recommended mod seems to be gears. So, I had 4:56 installed along with AEV lift and 35"s at the dealer. The gears cost about $1,500 out the door. I noticed quite a jump in power, especially off the line. Considering the increase in offroad performance as well, I'd say go with gearing first for the biggest bang for your buck.

RiverCityOffroad

My first was an 08 JKU that was wife's ride and we traded it in for something else for her. I bought an 08 2 door at the time because she didn't want hers beat up. Traded my built up 08 2 door for a 12 2 door, built that one up and then stripped it down when I decided I wanted to build a four door after I learned what I needed to about the 12+ 2 door. I traded that Jeep in stock and bought a 12 JKU that I still have.

I picked up an 08 2 door over the summer that needed a motor and I am building that one out to be a wheeling rig that I don't mind tearing up. I wheel my JKU, but there's always the lingering notion that I'm destroying a $50K+ vehicle.

/hi-jack

I couldn't agree more with those that are saying a re-gear will do more for instant return on power gains than anything else. A supercharger without the right gears won't be as exciting as one with the right gearing for the tire size.

Marcus

TheEngineer13

To keep in check with EPA regulations.

This is why the diesel needs to be made available. You can get a 4cyl turbo diesel to output 250hp and 300+ tq with ease and probably get better MPG (22-24). I got 19mpg in my stock F350 V8 turbo diesel with curb weight of 7200 lbs plus my 200lbs ass. Pretty sure if a TD Jeep could get upwards of 30mpg on the highway if it were geared right.

B 1000

As for MOPARs V8 conversion, I was completely unaware of that. Though I would wait to see if the diesel comes out before I pulled the trigger on engine swap options.

Oh did I say "higher"? I guess I meant longer ratio. But yes, his Jeep with same tires on 3.21 gears will out perform my Jeep with 4.10s in every way. Our Jeeps are practically clones other than his paint matched fenders, so I know it's nothing to do with weight. Also just last week I took a ride in a 2013 on 37s and that thing was a racecar in comparison to mine. In fact, his felt faster than mine did of the dealership floor with stock tires and all. So I've come to the conclusion that I have a crap pentastar.

PhxRainey

The gear comments are ALL TRUE. I would never suggest doing a SC before gears. I did 4.88 but regret it a little..wish I had put in 5.13

TheEngineer13

Well a higher number in gears (4.10 > 3.21) will take less energy (power) to move the same mass the same distance, but you will run out of RPM's quicker, and have to shift sooner.

Not sure if this is the issue you may be experiencing.

B 1000

I get what you're saying and I appreciate your help, but I have a good amount of experience with gearing and it's affect on vehicles. I had 3.21s on my JK before and went to 4.10s with a noticeable difference in "off the line" power. But it's still less than any other Pentastar equipped JK I've ever been it. I just have to suck it up and realize that my Pentastar is a fail and needs to be supercharged

palehorse

Yeah, it definitely sounds like something is wrong with your rig. With 4.10's, yours should definitely feel more powerful than your friend's 3.21 jeep (with all other parts being equal).

TheEngineer13

Are you still under warranty? I know some of the 12s had head issues. If you are take it back to the dealer. If you've got a bad motor and you put a SC on it you will do more harm than help.