Im looking at buying a 90 xj and i was wondering...

millertime · May 28, 2007

Im pretty sure it has the non ho 4.0l in it but id like the extra power of the ho motor. what are the differences between the two motors? Is there any way i could do a motor swap? or atleast swap the parts that make the differeance between the ho and non ho?

I have a spare ho motor with a brand new cam, billet valve train, high rev cam, long tube header/mid pipe, and all electronics i can pick up for 500 bucks with 80k on it.

let me know, thanks,
-Jesse

dizzymac · May 28, 2007

90' will be Renix. If the 90' runs good I wouldn't even bother going to the trouble of swapping heads and cams. If you do that you might as well go for a total rebuild. at the very least a re-ring would be in order.
I don't notice that much diff. between my Renix 4.0 and my H.O, at least not enough to go to the trouble of swapping heads.

millertime · May 28, 2007

dizzymac said:
90' will be Renix. If the 90' runs good I wouldn't even bother going to the trouble of swapping heads and cams. If you do that you might as well go for a total rebuild. at the very least a re-ring would be in order.
I don't notice that much diff. between my Renix 4.0 and my H.O, at least not enough to go to the trouble of swapping heads.

is there anyway to make the 99 intake mani fit on the renix motors? How bout a tb from an h.o.? id really like the added power of these things on there.

thanks,
-Jesse

88XJSport · May 28, 2007

What dizzymac said, there is NOT a noticeable difference at all between a "HO" and Renix. Don't bother. Besides, the Renix and HO use different wiring harnesses, different computers, and such. You would have to swap all of that out of you wanted your 5 or so tire shredding hp. Should have bought a 'Vette.

millertime · May 28, 2007

Well I have the total wireing harness, ecu, complete motor and trany, and its only got 80k mi on it compared to my 213k on the one in the jeep. Its already got the the cam, valve train, tb spacer, intake, 99 intake mani... I was just going to re-ring it, hone the block, and maby deck the head. It wouldnt be anything crazy but itd be a "fresh" motor.

I figured with the rebuild, performance parts, and complete wiring harness the swap wouldnt be to bad.

thanks anyways guys,
-Jesse

TiRod · May 28, 2007

The horsepower difference between the engines is due to turning the HO to a higher RPM - that's the way it's tuned.

Driving a 4WD in 4L, which is the whole point, is a low RPM endeavor through gearing and a properly designed torque curve.

So when Chrysler started adding hp to the Cherokee, they were playing an old game to attract less than knowledgeable SUV customers. And finally killed it off in their expert marketing opinion, to bring out the Liberty.

Horsepower adders like the HO head, the '99 manifold, headers, etc really don't do much when the thing is built to crawl with moderate lift in places no 'Vette could ever go - enjoy it for what it is, like all the 4 cylinder Wranglers on 33's. Happy Jeep owners.

millertime · May 29, 2007

TiRod said:
The horsepower difference between the engines is due to turning the HO to a higher RPM - that's the way it's tuned.

Driving a 4WD in 4L, which is the whole point, is a low RPM endeavor through gearing and a properly designed torque curve.

So when Chrysler started adding hp to the Cherokee, they were playing an old game to attract less than knowledgeable SUV customers. And finally killed it off in their expert marketing opinion, to bring out the Liberty.

Horsepower adders like the HO head, the '99 manifold, headers, etc really don't do much when the thing is built to crawl with moderate lift in places no 'Vette could ever go - enjoy it for what it is, like all the 4 cylinder Wranglers on 33's. Happy Jeep owners.

GOOD POINT!!! i never thought about it like that. thanks for the help guys! -Jesse

Im looking at buying a 90 xj and i was wondering...

millertime

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dizzymac

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millertime

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88XJSport

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millertime

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TiRod

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millertime

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