Jeep Garage  - Jeep Forum

Jeep Garage - Jeep Forum (
-   Performance Modifications (
-   -   WJ I6 Power Increase (

ubiquitousmatt 02-21-2010 01:38 AM

WJ I6 Power Increase
What is the easiest way to increase power output on a stock 4.0 I6?

00wj 02-21-2010 01:41 AM

Re: WJ I6 Power Increase
cold air intake, exhaust, programer, ported TB....

Joe in PA 02-21-2010 09:24 AM

Re: WJ I6 Power Increase
Sell it and buy a 4.7L HO. ;)

I've owned WJs with the 4.0L, 4.7L and 4.7L HO. Much as I liked the 4.0L in my previous XJs, the WJ is a whole lot heavier vehicle and needs a little more hp/torque. You can spend money attempting to squeeze a little more out of the 4.0L or you can spend a lot of money for a good bit of performance gains. An intake, throttle body, exhaust and tune will get you into the low 200hp range. A stroker or forced induction might get you into the high 200s. The easiest thing to do would be to sell the 4.0L and spend the money you would have used to tweak it on a 4.7L HO.

AcidCold 02-21-2010 12:34 PM

Re: WJ I6 Power Increase
Remove the "I" and give it a "V" with 2 more cylinders!
Lol seriously thought, the 4.0 has great potential if the axles are geared correctly. Cam, TB, CAI, Header, Cat-back and tune would be my weapons of choice along with a lower axle gear, I don't need top speed so low end power is where it's at.

NHWK05 02-21-2010 08:26 PM

Re: WJ I6 Power Increase
One thing that you need to remember about the 4.0. Its like a Diesel. Its more Torque then HP. Thats why even though the 4.0 may not feel like it has tons of HP, It will still throw you in the back of your seat because it has so much torque. Especially if you buy a TJ/XJ with a manual Transmission and the 4.0.

Its a great engine with tons of opportunity. Buy a CAI, Port the TB, Throw a Chip on it, and you should be quite impressed.

I know right now if i had to buy a cheaper vehicle to save money on payments but still have reliability i would buy any Jeep with the 4.0. You can easily put 250k on the odometer and keep it going another 100k if you treat it right.

I want so badly to get myself another vehicle with a 4.0I6. Most likely i will get a late model WJ in the next few years after the WK is paid off and give my fiancÚ (soon to be wife) my WK.

Chaoul1 02-22-2010 09:33 AM

Re: WJ I6 Power Increase
Stroke it to a 4.6L! :thumbsup:

That's the only way how to wake it up.

NHWK05 02-22-2010 09:36 AM

Re: WJ I6 Power Increase

4.7 I6 stroker

Denny boy 02-22-2010 07:26 PM

Re: WJ I6 Power Increase
run it into a tree and claim two of the cylinders fell off...... or do what they said^^^

FlyinRyan 02-22-2010 07:45 PM

Re: WJ I6 Power Increase
Give me a budget and I'll crank out something for ya.

I've got a 4.0 core sitting here on my desk.

ubiquitousmatt 02-23-2010 02:41 AM

Re: WJ I6 Power Increase
Thank you everyone, has anyone heard of a six speed manual transmission conversion kit for the WJ-NV242 [Selec-Trac]? I'd like to see that before, I start sinking money into it. Would this even be possible?

ubiquitousmatt 02-23-2010 03:10 AM

Re: WJ I6 Power Increase

Originally Posted by Denny boy (Post 156387)
run it into a tree and claim two of the cylinders fell off...... or do what they said^^^

Good idea, but I don't think my insurance guy will go for it. Heh, heh ... but that was a good one ... if boring out cylinder size is the way, I'd wait for the 4.0 liter to loose more than 40% of the stock power, spin out the odometer a bit more, before I move forward. That, plus a manual transmission conversion kit in a crate.

Chaoul1 02-23-2010 07:36 AM

Re: WJ I6 Power Increase
I haven't seen yet anyone put a 6-speed tranny in one.

All times are GMT -5. The time now is 08:11 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community