engine swap from 96 to 91 will it work?

i have a wrecked 96 jeep i know a guy who has a 91 i6 4.0 high output. head is blown on his. im wondering if my 96 i6 4.0 high output will be compatible with his 91. i have looked around on here without much luck im worried cause its a pretty specific thing. any help would be much appriciated.

thanks

Any HO block will interchange with any other HO block. Install the appropriate head/intake/exhaust/sensors as needed.

You can swap the whole engine with some trivial changes. The basic rule is that the electronics and fuel plumbing need to be the same year as the car in order for all of the parts to work, so in your specific scenario you will need to put the 91 sensors, ignition, injectors and fuel rail parts on the 96 engine, so that the computer and fuel pump and all that jazz will work as expected.

The other significant difference between 91 and 96 is that the later years had a different power steering bracket, pump, and belt tensioner setup, all of which bolted to the intake manifold a little differently. If you want to keep this stuff simple just keep the 91 setup, but if you want to switch on the new-style pump and tensioner you may need to swap intake manifolds (good time for a 99 since it is the same bolt pattern as the 96).

So basically pull the 91 engine out, drop the 96 engine in, put the 91 sensors, ignition, and fuel parts onto the 96 donor, and optionally replace the power steering assembly and intake manifold. There should not be any other issues

hey what about the ac compressor? would the one from the 96 go onto the 01 or is the 91 still usable?

Both compressors should bolt up the same, but the overall setup will be different. The switchover from R-12 to R-134a was in 93, and Jeep also changed the AC setup *a lot* over the years, including fittings, hoses, pressure switches, etc. Honestly if the AC in the 91 chassis is working alright then I'd just unbolt the compressor and lay it aside during the swap, then bolt it back on when finished. That way you would not need to discharge the refrigerant or have to mess with any potential conversion hassles. If it's not working, you can try removing the 96 parts and see how the fittings and such look after they have been disassembled then make a judgement call from there. The old hoses don't like to be removed

on the ac is there even a way to swap the motor and leave the ac system untouched it seems like it would have to be unbolted and lines unhooked for the motor to come out would like the ac system to be left alone im just wondering what the best way to do this would be maybe where to set the pump so that it is out of the way like you suggested
thanks so much sorry for all the questions


caleb

I've done it. I used all the brackets, AC compressor and old intake manifold from the old motor. Seems like something was different with the distributor too but I could be wrong, it was 5 years. Keep your old motor to compare and take parts from until your done.
The '96 motor seemed to run a lot stronger the old motor.

When I did the 99 swap into my 91, my existing AC didn't work and the condenser had a big hole in it, so I uninstalled everything then reinstalled afterwards. If yours is working and you want to keep it charged up then you will need to unbolt the compressor from the bracket then lay it over the passenger fender (use a rope on the hood hinge if you need extra support). Otherwise you can unbolt and look at the stuff. I had to replace my condenser, drier, and a couple of hoses before the A/C started working so it wasn't a big deal for me.