Vehicle: 1984 Jeep CJ-7
Engine: 258ci AMC Straight-6
Injection: Multiport manifold and associated components from '93 Cherokee 4.0, but still using the 4.2 cylinder head
Description: Currently running Megasquirt I on a 2.2 version board, with a GM HEI distributor from an I6 Chevy.
Status: Running and driving, but only beginning the long tuning process right now. After that, it's time to slowly go back and re-do all the crimp connectors in the harness with some proper solder and heat-shrink.
Future Plans: Probably next summer will be a 4.0 cylinder head swap, as well as a 1999+ style intake manifold.
Pictures to follow in a few days.
I have a friend with a 1994 (?) Jeep Wagoner here in the Philippines bought ex-military from Clark Airbase in Pampanga. It has a 4 liter straight six with multi-point fuel injection. Recently the injection control unit failed. Is this engine similar to yours? Would it be feasible to replace the control unit with a MegaSquirt unit? Would you recommend we try this?
Thanks a bunch,
i swapped a 4.0l into an 86 cj7 and couldn't get anything but the 4.2l intake to fit with the brake booster .. tried a renix intake, a early mopar and the 99+
1. Unfortunately I don't have any pictures. Due to other issues, unrelated to the Megasquirt, I parted ways with this CJ-7 a few years ago. I also no longer have the computer that had the tune files I had been using.
2. Regarding fit issues on your CJ-7. Part of the problem may be that the intake ports on the 4.0 head are about an inch or so higher than they are on the 4.2 head. This would raise the whole intake up by about the same amount. I know there are people out there swapping the 4.0 into CJ's, but I have never done it myself. My swap used the original 4.2 head, never got around to a 4.0 head swap.
3. The '94 engines are a much later design than the 258 I was using. Essentially, the 258 I started with had a carburetor and massively complex vacuum system for emissions. The later 4.0 always used fuel injection in one form or another, and later designs were distributorless. I don't know if the '94 had a distributor or not, if it DOES have a distributor it would be a fairly easy conversion, so I would try it. (though I do realize I am replying 4 years after your post).