3.8 snail retool options

[OS-Aussie]

Ok, we had our views on the otherwise leisurely performance of the JK, what options do we have ? Let's take the ever present open heart transplant of the table and talk bolt on solutions.

I have the stock auto Sahara with stock tires and wheels. The stock JK down shifts at the sight of curbs and I want to tow with it.

Mods to date include a Gibson Exhaust, Uni Chip Tuner and high flow filter. The mileage is approx 20mpg on the highway but it still will not pull the skin off custard.

Overdrive does appear to be too high for the rev gear combo from the factory and getting bigger tires would make this worse.

What have others done, who tow, and what appears to have made the most difference? Torque appears to be the biggest missing part of this story. :smiley_drive:

 

[wanderer-rrorc]

IVe heard the programers really make a diffrence (edge I think)

I traded from an auto to a 6spd (and 2 extra doors)...and the 6spd REALLLY wakes up the 3.8...

 

[Hilldweller]

I'm using 4.56 gears; couldn't live with the 3.73 stockers.
I tow and got rid of the Sahara wheels for 16's. 285/75-16 MTR/kevlars now.
4.88 would've been better for me though; it's hilly around here.

 

[XXXpedition]

What have others done

i bought the diesel and chiped it. (comes with 4.10 gears)
now 220 HP and beyond 360 torque

 

[OS-Aussie]

i bought the diesel and chiped it. (comes with 4.10 gears)
now 220 HP and beyond 360 torque

Hate you !! Well ok, not you Jeep's market selection of power plants. :ylsmoke:

Yep, the 2.8 diesel would be better, even more so with a trailer.

 

[XXXpedition]

we might be able to get the cool power plant, but we cannot do anything really cool with the rigs otherwise - TÜV is ALWAYS getting in the way! ;-)

 

[JKDetonator]

Regear!

You have to install lower gears in your differentials! It is the only way to properly utilize the miniscule power/torque created by the anemic hamsters they have in that engine. I went from not even being able to use 6th gear and downshifting to 3rd on hills to being able to pull trailers uphill in 6th with the installation of 4:88 with 35" tires. There are aftermarket superchargers, chips, etc. but they all require power in the upper rpm range. Regearing will allow you to utilize the power band as it was meant to be used. Several companies offer lower gearing for about $500 per axle (both axles?) and it cost about $1000 to have a reputable mechanic install them. Still gets lousy gas mileage ...:elkgrin:

 

[Hilldweller]

This product is supposed to be a big help:
http://www.youtube.com/watch?v=b9XAC-BvUyo
http://www.soundracer.se/

 

[getlost4x4]

keep telling yourself

there is no replacement for displacement!:elkgrin:

or add a turbo.

 

[Backwoods Rambler]

Aren't there a few superchargers available?

 

[Hilldweller]

Aren't there a few superchargers available?

Forced induction is certainly an option.

http://www.rippmods.com/Products_offered_for_07_08_Jeep_JK_s/259.htm

 

[Summiteer]

This is an option I've been considering: http://www.pirate4x4.com/forum/showthread.php?p=10971268

They take a stock throttle body and bore it from 63mm to 69mm. They offer a 100% money back guarantee so there's not much to lose.

I'd still like to see some dyno numbers before I commit though.

 

[getlost4x4]

it won't do anything.

really the best options are:

Gears- cheapest option

Engine Swap- expensive

Forced induction- expensive

get a vehicle with V8

 

[Root Moose]

it won't do anything.

really the best options are:

Gears- cheapest option

Engine Swap- expensive

Forced induction- expensive

get a vehicle with V8

Quoted for truth.

There is no silver bullet magic to producing more power. On a dyno, sure you might se a few hp. BFD