86 Comanche 4 cyl 5 speed is this a GM engine?

[dotis]

I have a 86 Comanche with 2.5 liter tbi, 5 speed 2x4 is this the same as a GM Iron duke or is this a jeep engine?

[Pete M]

It's an AMC engine. But it does have the 60* GM transmission bolt pattern.

[mjeff87]

The "2.5" is actually a 2.46L, and is an AMC engine. AMC purchased some GM Iron Dukes, but installed them only in some Pontiacs and Eagles, not in XJ/MJ's. The AMC "2.5" is actually a shortened version of the 4.2L, and shares most all the same internals....rods, pistons, timing set, etc.

 

Jeff

[carnuck]

While the bolt pattern is the same on the bell as the 2.8L V6 and later GM 4 cyls (early 2.5 Dukes have the same bell as Chev V8 ), not much else interchanges.

If you can find a pre '83 CJ with the 4 cyl with V8 pattern and auto, the 904 trans used can be beefed up to put a smallblock Chev into an XJ.

[carnuck]

The "2.5" is actually a 2.46L, and is an AMC engine. AMC purchased some GM Iron Dukes, but installed them only in some Pontiacs and Eagles, not in XJ/MJ's. The AMC "2.5" is actually a shortened version of the 4.2L, and shares most all the same internals....rods, pistons, timing set, etc.

 

Jeff

 

I think you meant Spirits and Eagles. They also used them in CJs and DJs before '83. The 2.5 is made of the same parts as the 4.0L, not the 4.2L. They even share pistons, but not rods. BTW, the AMC 2.5L came first (mid '83 in Eagles, Spirits) and the 4.0L is a designed extension of that motor. ('87)