4.2 in a cherokee

[dlh9350]

I have tried searching through old threds but came up empty. Wells heres what I have, I have an 87 cherokee with a bad 4.0 motor. I found a guy who has a 4.2 out of an 87 wrangler. What I was wondering is how differant are the blocks, would I be able to use in in my cherokee. Could I just use the short block out of the wrangler?? Any help would be great.

[xjy173]

I've been a member of this board since 1999 and I've never heard of anybody swapping in a 258 into a XJ. I would advise you to consider rebuilding your 4.0 or look into finding another one from 1987-90. Good Luck!!

[krabysniper]

I'll go one better. You have the crank shaft you need to do a stroker of the 4.0. Do a search, on google or even this site, of stroker 4.0. You'll find tons and tons of info on the subject. Your going to need to rebuild the 4.0 anyway and the cost will only be slightly more than a stock build, but the torque and horsepower are worth it. Thats if your into that kinda stuff that is.

Here is a few just for starters.

Stroker

From Junker to Stroker

[JeepDawg]

I ran a 4.2L block under the 4.0 head on my wife's Cherokee for 3 years without any issues. Except for a mounting stud on the side of the block for the alternator, everything bolts up fine. You do NOT want to run the 4.2

The 87 wrangler was carborated...the Cherokee has the Renix fuel injection. Intake and exhaust are totally different.

So, yes, you can use the 4.2 block...have the 4.0 head rebuilt and your good to go.

However...unless your getting the 4.2 really cheap AND it's in good shape (and low mileage), that may not be your best choice. Add up the cost of the head work, cost of the 4.2 and add about $100 for misc parts. If the new engine is low mileage and the above cost is less than $1000, then it might be the best way to go...but if it's near or over $1000, then you would be better off having your engine rebuilt.