1999-2000 4.0 into 1992 Cherokee?

[EvilMoose]

Hello again, long time no speak....

My sister owns a 1992 Jeep Cherokee Laredo with a 4.0 H.O. and auto transmission in it. She's almost quite literally melted the motor down in it (melted head gasket, three pistons with vaporized ring lands, etc), so I'm going to swap the cooked 4.0 out for another engine....and I've located a 4.0 out of a 1999-2000 ZJ Grand.

My first question: will this 1999-2000 4.0 work in the 1992 Jeep (I'm told the motor is a 2000 model, in a 1999 jeep...)? I recall the 1999-up 4.0's got superior intake manifolds (worth 20+ HP or something), but I don't recall anything out of the ordinary being different....does anyone have any thoughts as to problems I'm going to run into if I use this engine? I don't want an $800 mistake....and I would appreciate any advice any of you might have.

 

[jps4jeep]

the manifold is a better design, but 20 hp is a little ridiculous. more like 1-2 hp if any measurable power increase. you biggest obsticle will be switching from ODB 1 to ODB 2. the easiest way to get around this is to use as much from the original motor as possible (sensor positions, ECM, Exhaust) the other big difference, I believe all WJ's got a coil on cyl distributor free ignition system. adapting this system to work with a ODB1 system might be a little taxing. if the motor has a single coil with a distributor, then run it.