cj-7 4.2l to 4.0l

[jeepdude89]

I have an 84 CJ-7 and the motor that was in it was the 258 4.2L motor and my brother and I were goin to just put and 4.0L head on it and then put a mpi on it but then while my brother was down here from idaho we went to mepco and they said that doin it that way would take a lot of time and money :sick: and said we should just find a complete 87 or newer 4.0L and drop it in so now we dont know what to do and has any one done this kind of engine swap before? any advice would be nice thanks

 

[DaveB]

I have an 84 CJ-7 and the motor that was in it was the 258 4.2L motor and my brother and I were goin to just put and 4.0L head on it and then put a mpi on it but then while my brother was down here from idaho we went to mepco and they said that doin it that way would take a lot of time and money :sick: and said we should just find a complete 87 or newer 4.0L and drop it in so now we dont know what to do and has any one done this kind of engine swap before? any advice would be nice thanks

I did this swap on my 84 cj8. I used a 99 TJ 4.0 with 93 XJ wiring and injectors. There is a good forum for this swap on cjoffroad.com. The 4.0 will bolt right up to the same motor mounts and tranny. If you use your old tranny you have to figure out where to put the crank position sensor. Hesco sells a crank position sensor relocation kit that moves it to the front of the engine. I used an AW4 auto from a Cherokee which already had the CPS mounting location. Feel free to send a PM or come on over and look at mine, and I can fill in more details.
Dave

 

[Jay5.9L]

I have a 4.0L swap in my CJ and its very nice. Dave B is a great source of info about the swap so keep his number handy LOL. I would look for at least a 91 or newer 4.0L because they are the H.O. versions. Also I think Dave B told me that the later engines had OBDII which makes the swap harder. Good luck

 

[jeepdude89]

thanks for the help guys this will help a litte bit we still dont know what exactly what we're doing
daveb where do u live so i can stop by sometime? thanks a lot guys

 

[DaveB]

thanks for the help guys this will help a litte bit we still dont know what exactly what we're doing
daveb where do u live so i can stop by sometime? thanks a lot guys

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