Jeep Comanche Project

Though I'd share one of my other projects.

Currently I’m working on my 1989 Jeep Comanche with a 4.7L stroker 2WD, and 5 speed. I started the engine project back in 2003 for another Jeep while I was at college. As a student at UNOH I was able to do all my own machine work and assemble the motor myself. (i'll post more specs below) By the time I got back my Cherokee had rusted out and it was time to find a replacement.

I picked up the Comanche sometime around 2005. It had 101,000 miles but the motor was junk. Body was pretty rust free with just a few dents. So for a few hundred dollars I dragged it hope with the intentions of dropping my stroker motor in. When I started working on the truck and pushing it around the yard there was some odd clunk when turning. I guess at some point the truck as hit in the front and there was a poor repair done. The subframe was welded but then cracked around the steering box. Instead of welding it back up I cut the outer part of the subframe back and welding in a new part from a parts Cherokee.

A month later after I fixed the subframe I had a tree branch land on the front clip.

Fenders, hood, and header panel had some damage so I decided to start swapping on a 97+ front clip

Here is a picture shortly after getting it running for the first time

As for the engine here is everything I can remember:

-1995 4.0L block bored .60 over
-4.2L crank polished and balanced
-4.2 rods with ARP bolts, removed and polished parting lines
-SpeedPro hyperutectic pistons with coated skirts, dished and rebalanced
-1994 4.0L head, backcut valves, 3 angle valve job, cut spring pockets, Chevy Z-28 springs with shims, ARP head studs, lots of port work.
-Double roller timing chain
-1995 Jeep Grand Cherokee 25 lbs injectors
-2001 4.0L intake
-Crane cam, either 260/272 Advertised Duration, .456/.484 Lift or 272/284, .484/.512, I forget what I went with.

Now that I've dragged the truck out of the woods and to my new place I've started working on it again. Most of the paint has flaked off the engine and the truck is moldy inside and out. The computer issue was still a problem so I decided to go with megasquirt. Install went smoothly once I found the correct ford shutter wheel to go inside the factor distrubutor. Since I've already megasquirted our Challenge Jeep the wiring was not bad either. There was also no shift computer to mess with and rewire since this Jeep is a manual.

So the Jeep finally runs again but this time correctly. It Idles and revs smoothly but still need some tuning. Biggest problem I have right now is that I can't sit in the Jeep. I'm currently working on making brackets for a set of WRX seats. Once thats done I can do some tuning.

Not really sure what my goal for the truck is. The challenge has crossed my mind since everything so far is under $2000 but all my receipts are gone and I'm not sure how to count the machine work I did at school. I also happened to pick up a 60 trim T3/T4 turbo and 36 lbs injectors. Might be fun to show up with 2 turbo Jeeps or I can swap in 4wd, add a mild lift, and just tow the Cherokee.

Looks fun. Ive been 'planning' a jeep buildup for years. So far i've sold the first 3 cherokees i owned thinking they werent what i wanted, then decided they were what i wanted, then picked up a cherokee that needs more work than any of the previous ones, and maybe this time it'll stick.

Cool. AMC forever!

Awesome to see you still have it and are interested in working on it again.

Love the Commanche cool truck and th 4.0 inline 6 is an awesome engine

Nice! I have an '87 Comanche 2.5/2WD sitting here with a dead cylinder. Was planning to swap in a Dodge 2.2 Turbo I using bits and pieces from a 4cyl Dak parts truck, but it might get a 5.9 Magnum now. It's intended to become my shop truck.

I also picked up a '96 2-door Cherokee Sport as a parts car. Was a 4.0/5-speed 4x4. Got it with no motor/trans/transfer case or gas tank. Was a donor for a Wrangler. It needs floors but otherwise is in really good shape. And it's sitting right next to a '95 Dak 5.2 4x4 parts truck in my yard. While I'm trying to sleep at night I hear the Cherokee asking for the Dak's drivetrain. I need to pull the interior and see if I really want to dive into it.

Haven’t made too much progress this summer. My biggest problem has been trying to make seats fit in the truck since the transmission tunnel get in the way. I have not seen any Comanche’s in the junkyard and Cherokee seats don’t really fit. I was going to make custom brackets for my WRX seats but I then found a set of used Corbeau brackets. Even with the brackets the seats sit way too high. I might try removing the sliders to try and gain some clearance. If that doesn’t work I’ll have to find some aftermarket seats.

Other then that I’ve bolted on the rest of the front clip and I’ve found a drivers side 97+ Cherokee door. Still working on getting the door striker pin lined up correctly

I love those trucks.

PseudoSport wrote: Haven’t made too much progress this summer. My biggest problem has been trying to make seats fit in the truck since the transmission tunnel get in the way. I have not seen any Comanche’s in the junkyard and Cherokee seats don’t really fit. I was going to make custom brackets for my WRX seats but I then found a set of used Corbeau brackets. Even with the brackets the seats sit way too high. I might try removing the sliders to try and gain some clearance. If that doesn’t work I’ll have to find some aftermarket seats. Other then that I’ve bolted on the rest of the front clip and I’ve found a drivers side 97+ Cherokee door. Still working on getting the door striker pin lined up correctly

Don't know all the differences between Comanche and XJs but I had a similar situation w/ fitting seats in an XJ. The trans/ t-case floor hump and oddball seat mount bolt spacing made it difficult for other makes or aftermarket seat mounts/ sliders. I used the factory XJ seat mounts, fabbed minimum rise adapters for Summit Poly buckets and they were still over a cpl inches higher than factory seat height but they did work w/ a tilt wheel. The added seat height did work well for a lifted vehicle and off-road. I dunno if the tilt columns are interchangeable, might be worth a look tho.

A friend built a similar motor for his wrangler. It'd pull the front wheels.

Wranglers are actually pretty good at wheelies. Massive weight transfer helps.