Head swap for an 85 cj7

[themazq]

Hello, I would like to know if I can fit the cylinder head from a 98 cherokee on my AMC 258 i6 / 4.2l . It seems like the best heads are the 93 or 94 but I haven´t been able to get one in a decent shape. I read a thread somewhere from a guy that did put the 98 head, but I cant find it. I´m also hoping to get rid of my 2bbl carter once and for all and trying to put the mpi from the same 98 engine. I´m on a tight budget so buying the mopar at $2.400 is out of the question. Thanks everybody.

 

[IOPort51]

I think thats something "this guy you know" was doing. I think he even got it working. check it out, a 4.0 head on a AMC 258 i6 / 4.2l with the injection system. Pretty incredable stuff if you ask me.

 

[BrockGrimes]

See post #15 this should get you headed in the right direction:
http://www.jeep-cj.com/forums/f49/useful-info-thought-id-share-665/

 

[themazq]

Thank you, I think I'll wait till'I get a head from an older model. It seem like it's more dificult to do the swap with newer heads. I'm not really an expert in mechanics but I think it has something to do with something called "obII", wich I'm not really shure what it means.
Anyway thanks a lot.

 

[Sasquach]

Hello, I would like to know if I can fit the cylinder head from a 98 cherokee on my AMC 258 i6 / 4.2l . It seems like the best heads are the 93 or 94 but I haven´t been able to get one in a decent shape. I read a thread somewhere from a guy that did put the 98 head, but I cant find it. I´m also hoping to get rid of my 2bbl carter once and for all and trying to put the mpi from the same 98 engine. I´m on a tight budget so buying the mopar at $2.400 is out of the question. Thanks everybody.

What casting # is the head? it can be found on the top center area, 7120 is the most desired but others will work.

 

[Sasquach]

Thank you, I think I'll wait till'I get a head from an older model. It seem like it's more dificult to do the swap with newer heads. I'm not really an expert in mechanics but I think it has something to do with something called "obII", wich I'm not really shure what it means.
Anyway thanks a lot.

obdI and obdII are the electronics and refers to On Board Diagnostics. the Mopar system is obdI and is the same as a 94 wrangler, All the junkyard conversions I have read about use the obdI as well and I think it is a bit simpler but can't say for sure.
The head has nothing to do with this so you still may be able to use it, it could be #0331 and I have read that one is useable on the AMC 258 i6 / 4.2l .
This is a VERY worthwhile project to take on so don't back away.

 

[ThisGuyUKnow]

PM me and I can educate you all day long on the MPFI and 4.0 junkyard swaps. My swap ended up costing in the vicinity of 1500 bucks. We used a 4.0 head from a 1995 (the head casting you are referring to is found in 1991-1995 4.0s) the wiring and ecm from a 1994 xj and the intake I found on a 95 grand cherokee. I also swapped in the whole Serpentine system from a 1991 xj. If you are willing to collect the parts even with low mechanical skills you can do this I promise you and Me and sasquatch should be able to work you through all of it.

 

[themazq]

PM me and I can educate you all day long on the MPFI and 4.0 junkyard swaps. My swap ended up costing in the vicinity of 1500 bucks. We used a 4.0 head from a 1995 (the head casting you are referring to is found in 1991-1995 4.0s) the wiring and ecm from a 1994 xj and the intake I found on a 95 grand cherokee. I also swapped in the whole Serpentine system from a 1991 xj. If you are willing to collect the parts even with low mechanical skills you can do this I promise you and Me and sasquatch should be able to work you through all of it.

Thank you guys. I'm going to get started and collect the parts and then keep you posted.
I'm not a mechanical expert but I've done some work in some other cars. I'm only worried about the wiring and electrical stuff.
Thanks again.

 

[Sasquach]

Thank you guys. I'm going to get started and collect the parts and then keep you posted.
I'm not a mechanical expert but I've done some work in some other cars. I'm only worried about the wiring and electrical stuff.
Thanks again.

Good idea!
The head swap is easy enough but you will need and want to rework the exhaust, I used a 87-90 cherokee header and you may have a slight issue with your head bolts being the wrong size and will need either spacers or retapping the block or new head bolts(easily solved).
The electrical is no problem the way I went with the Mopar kit but you could still buy just the harness ready to plug in if not ready to try transplanting a harness from a donor.
ThisGuyYouKnow is your junkyard specialist and your resource there.

 

[ThisGuyUKnow]

my dad is the electrical guru in my corner. If you feel that you just can't do the junkyard wiring he may be able to help label/thin out one for you for a reasonable price. Other than that dude honestly the most intimidating part is the wiring the rest is just bolt on.