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Websites for Transplanting 4.0L into 85 CJ w/258?

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I am having trouble figuring out some of the details for transplanting a 94 4.0L in to my 85 CJ that has the original 258 in it. For example, where to mark the bellhousing of my existing T-176 as to cut it for the sensor to pick up spark timing. I assume I use the 4.0L flywheel. Also, recomendations for and external fuel pump are needed. Lastly, any "tips or tricks" for matting the 4.0L engine wiring harness and computer to the 85CJ connections? Have I over looked anything major here for this swap? I never done a swap before so any info or websites to view would be of big help. Thanks. :)

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Well I don't care much for advance adapters, too pro chevy, but there catalog has an article in the back all about doing the conversion your talking about. Steve

Here is a link to my page illustrating the MPI style fuel pump/filter setup and fuel line routing on a CJ-7 System.htm
I can't help you with the bellhousing sensor.
Haven't seen a page like that on the web.

as for the bellhousing location, you can skip that part and go to clifford performance for a new crank pulley that has the sensor integrated into the kit. am getting ready to transplant a 97 xj 4.0L with 8000 miles into my 83 cj7. been looking around alot and not much out there on jeep to jeep conversions. he's right about a/a, very chevy oriented. anyhow, the t-176 is a medium duty tranny that should hold up well under the new power, as long as your foot is light and the tires are right. i get mixed answers on the motor mounts, and i've heard that a company called hesco makes some sort of wiring supplement for these conversions, check it out. let me know how it goes. steve-0 (mudncj)

There's some info on my site at
I haven't seen anyone ever detail exactly where to drill/cut the bellhousing to use the flywheel sensor, however you can substitute a crank sensor like what Mopar uses in the 4.2 MPI kit instead. Yes, you would use the 4.0 flywheel. offers the conversion harness.
There's an article in the Jeep-tech-transmission-conversions section on Off-Road.Com where Dave Moulton puts an SM420 onto his 4cyl YJ. Dave cut the crank sensor into an S-10 bellhousing in this article. A freind of mine was able to use this info last week when he mated a Ford T-18 to a 4.0 using a CJ bellhousing. He says it works fine.

I did this to mine, and it works fine. I just built up the area around the bell housing, and cut and tapped for the holes. I just built another bell housing for a friend putting in a 4.0 in his '83 cj-7. This time I cut the entire area from an ax-15's housing and wielded in the whole stock piece using the bolt holes to locate it. There is also one other small problem that you will have to contend with. The flywheel for the 4.0 isn't as deep as the 258, and you will have to drill out the pivot for the fulchrum, tap it to 1/2 by 20, and screw in a stud to correct the length.

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