4.0 swap

[Ejm]

Will a newer 4.0 l bolt up to a 80 CJ7 with an automatic? Just wondering if the bell housing bolt holes are the same

 

[mtnwhlr]

Yes

 

[ThisGuyUKnow]

Will a newer 4.0 l bolt up to a 80 CJ7 with an automatic? Just wondering if the bell housing bolt holes are the same

yes and no. Any year 4.0 will mate to your tranny no problem. 99 up 4.0s changed the motor mount configuration so they do not bolt right up to the AMC 258 i6 / 4.2l mounts. SO the later 4.0 s are no more bolt in than a chevy or ford engine would be in that youll have to customize your motor mounts. Early 4.0s should work no problem.

 

[Ejm]

And are the 93-up HO motors? Thought I heard that also?

 

[mtnwhlr]

I think they are 91-97

 

[ThisGuyUKnow]

And are the 93-up HO motors? Thought I heard that also?

I believe any past 91 are considered HO thats 91-06. Although I think after 95 they stopped using the HO tag. HO refers to the redesigned head that came out in the 91 models. They also redesigned the injection system that year as well.

Everything I have seen indicates that the bottom ends of the pre 91 4.0s are the same. So you could easily get say an 89 4.0 block and use a 4.0 head and injection and see the same results.