What is the best and cheapest way to gain a little horse power. also my jeep jumps out of overdrive a lot on the highway. Do I need a new gear I have a 08 4 door sahara on 315in kumho mud terrains with 17on xd hoss rims.

 

Simple answer: Regear
Costly Answer: Hemi Swap

 

Lack of power is a terminal illness with the 3.8L. Hemi or Regear will help

 

A Superchips programmer might help you with the overdrive jumping in and out, but the real answer is to regear. I know you want a cheaper answer but there really isn't one out there. The programmer will also allow you to recalibrate your speedometer/odometer which is very helpful.

My 35 BFG's are off enough that when the odometer says I have gone 5 miles I really have traveled 6 miles. (GPS) When I check my mileage I divide the reading by 5 and then multiply the answer by 6 to give me the real miles I have traveled. Yours may be different than this but this just shows how far off your mileage can get.

 

CAI, exhaust, chip - Not really worth money

Ripp SC - V3 is $4800 - gives you min 100 hp gain.

Hemi - $18000 - Costly, gives you serious jump in power, but serious work.


Personally I'm prob going to do the Ripp SC. Hemi is just too much money..

 

How does a hemi swap cost that much? That a crate srt engine, someone else doing the work, etc etc?

 

Browse any of the dozens of hemi threads on the Xtreme Tech forum above this one. You'll find that it is not a straight-forward 'drop in the new motor and off you go' swap. You've got 9 or 10k in parts alone, before you even get to the labor.

There was a pretty good write-up a while back from someone that did the swap in his garage. Pics from stripping his JK down to the frame, all the way through the new engine/transmission/etc install. Worth looking it up if it interests you.

 

I dont know how many of you guys have owned Jeeps previous to the JK but everybody keeps talking about the lack of power in the 3.8 and I am wondering what you are comparing it too? A corvette? of course it is under powered compared to that but compared to the 4.0 and the 4.2 it is better in some ways and not so great in others, but I would say mostly better. every member in my (large) family owns a jeep from CJ, liberty,TJ, JK and I have also owned them all from a 1973 J4000 to my third 2009 JK. anyway, the 3.8 drives different from the 4.0 for sure but if you learn how to drive it is actually better than the 4.0 and even if you have a 300hp Hemi you still need to regear if you put 35's or bigger and you have 3:73's or higher.

Anyway the point is 3.8, 4.0, 4.2, 5.7, 5.9, 6.1, 0r 6.7 you should still regear it if you are putting bigger tires on it, in my comp buggy with a 5.9 I still had 5:13 gears.

Sorry that is just my two cents on the subject, I get tired of everybody whining that the 3.8 is so gutless, of course it is with 35's and 3:53's!!!!!!!!!!

 

If you can't afford to go Supercharger or Hemi, then a CAI, exhaust, Superchip Programmer, will make a noticeable difference. Then if you have the $$ and want to regear as well, then you should be pleasantly pleased. Or do the regear first, then add the other goodies. Either way you should like the upgrade. Most that I know that have just gone with the CAI, exhaust, and SC programmer, have been glad they did. I still need the exhaust, but just the CAI and programmer, have made me happier with the noticeable performance gain.

 

A Vette, no. A LS1 Camaro and 454 V8 Chevy truck....yes. Makes my JK feel pretty "slow" when compared to the other vehicles I currently own.

In all seriousness, the JK is underpowered for a SUV in it's class/size. I wouldn't trade my Rubicon for anything else on the market, but the "competitor" vehicles (though not up to the cut in off-road performance), do offer much more power and faster acceleration (not counting the I-5 H3). Most JK owners spend more time on concrete than slickrock, so increasing performance does become an area of concern. It's no fun to get on the interstate and wonder if you'll have a semi up your a$$ before reaching the speed limit.

As for me.....I expected the Jeep to be a performance slug from the day I bought it. For me, it's part of owning a Jeep. I drive my Camaro once a week to cure the power woes BUT...... there is a Hemi swap already planned once the last payment for the Jeep is mailed to the bank