I have an AMC 4banger in my 89 YJ. It came with the Renix TBI, which cannot be modified much. I am replacing the engine right now, since the last one dropped a valve recently on a normal shift into third gear. Boom, chugga-chugga. No va.
I'm replacing the Renix TBI with Mopar MPI from a '95 XJ 4banger, and using a '97 Dakota bellhousing, which has an external slave cylinder rather than the infernal internal slave, to allow me to mate the AMC-designed 4banger to the better AX-15 six cylinder Jeep transmission. Since that transmission shares parts with a Toyota R-150 5-speed, I'm using the tail portion of an R-150 to mate up a Marlin Crawler doubler and a Tacoma transfer case. I'll have to move the engine forward to get the entire package to fit under the Jeep, and am also stretching the wheelbase rearward.
On the engine build for this "2.5L H-O", I ported and polished the head, and am using some yellaterra roller tip rockers, along with a 4.o TB and some 24lb/hr injectors, and a Banks stainless header. Should move the Heep around pretty nicely with these mods.
The AMC 2.5L is a great lil engine, kind of like a tractor engine, like its father, the almighty 258! I love the way the 4banger has a throaty "european sports car" sound to it when exhaling through a Flowmaster 40 series.
I know, for the amount of trouble I'm going through for this swap, I coulda had a V8, but I have always liked the AMC 2.5L, its just so simple and reliable.