Ok i'm sure you guys will give me flak for this post but whatever... I want to build a comanche I have a line on one that is a 2.4 4speed but I would convert it to a auto 4liter. Is there anything i want to stay away from. I don't know shit really about them and unfortunetly I can't search so any info will help......

Well I once upon a time helped put a 4.0 where a 2.8 Six used to live. Wiring was hell, still isnt all the way sorted out. The mounts bolt up, it might be easier since you are going from stick to auto instead of visca virca, especially if you get a generic floor shifter. Most of the parts will bolt over, be prepared for some frusturation and long nights.

I'd skip the 4.0 and get a V8.

^^^what he said^^^

If you are going through the trouble of an engine swap, you might as well do the v8 and be done with it.

I got a buddy thats swapping in a 4.0 and hes having a hell of a time tryin to get it to work. i guess that the alarm shit on it is the problem.

after a couple nights he said he shouldve gone to the v8. you can always do fuel injection later, and it would be easier with the plug and play stuff from howell, edlebrock and companies like that:smokin:

There's a lot to consider when swapping a V8 into the uni-frame construction of the MJ's and XJ's. Definately want to consider some sort of frame strengthener.

If you do the 4.0L swap get a complete XJ thats what I did and it was cake. I took everything from the engine the too the dash and all the wiring. The MJ is basically a XJ from the grille to the front seats. Mine was a 86' 2.8L and I put a 94' 4.0L auto in it.

after a couple nights he said he shouldve gone to the v8

i siad i shouldve gone with a 4.0 half way threw.

There lots you can get from the junk yard when swapping a jeep product into a jeep product. From exsample motor mounts, cross members, hoses, throtle linkage, clutch setup, power steering( and lines) rad hoses, drive line set up, auto linkage,auto cooler lines , wiringing (thats fits) fuel lines, Exhusted. Drive shafts. ect. If you go V8 route all that^ and more would have to be customized , or fabricated.


In my opion i would go the 4.0 route inless you want your jeep to be out of commession for a while. and spending 30% more time and money then planed.

But i strongly recomed serching all you cant before starting(maby try searching 4.0 in to yj, same jist) it's better to get discouraged Before you start then get discouraged half way threw and end up sending it all to the wrecker.

lots of info here comancheclub.com and the 86 year had a lagre fire wall cause the only options were a 2.5 or 2.8 motors so a 4.0 is a tight fit storm:trooper:

after a couple nights he said he shouldve gone to the v8

i siad i shouldve gone with a 4.0 half way threw.

There lots you can get from the junk yard when swapping a jeep product into a jeep product. From exsample motor mounts, cross members, hoses, throtle linkage, clutch setup, power steering( and lines) rad hoses, drive line set up, auto linkage,auto cooler lines , wiringing (thats fits) fuel lines, Exhusted. Drive shafts. ect. If you go V8 route all that^ and more would have to be customized , or fabricated.


In my opion i would go the 4.0 route inless you want your jeep to be out of commession for a while. and spending 30% more time and money then planed.

But i strongly recomed serching all you cant before starting(maby try searching 4.0 in to yj, same jist) it's better to get discouraged Before you start then get discouraged half way threw and end up sending it all to the wrecker.

Ya I hear that Iam all about the straight swap in I hate tryin to fab or find misc. parts to make things fit or work. If I do it for sure gonna be the 4.0 I'm just up in the air weather I'm gonna buy this one that I found for cheap that I would have to do a swap or just hold out for a smokin deal on a stock 4.0 one... I already have one god damn project with my 4runner i really want a comanche but it will just be another spot in the garage taken up for awhile... I don't know!!!!!!!!!!!!

Are you planning on it still being street legal?

Yo might want to look into your emissions laws. In AZ you can only swap in an engine with the same number of cylinders that was offered from the factory, make doesnt matter. For example, CJ7's in the 70's and early 80's had the 304 V8 option, so i can put a chevy v8 in my 79 if i want to (and plan to). If i had an 86 i would be SOL.

The same would hold true on you MJ and an 8, it never had the option.

Like i said, check your laws, but something to think about

.02

I live in oregon they don't care as long as it passes DEQ thats all they care about and there are even ways around that if you are smart....

Of all the rigs my buddies and me have ever had, the commanche for some reason is still one of my favorites. The wheelbase and weight distribution is great and parts are everywhere for them. His had a 4.0 that always did fine. I would prolly consider a V8. He wheeled the hell out of that thing for years and finally sold it when his cab started breaking apart in the door jams from flex. If it had been setup right with a subframe connecting everything and mounting the long arms it would have been fine. Instead he did some leaf springs in the front (don't ask me why) and it wasnt reinforced for wheeling.

Are you planning on it still being street legal?

Yo might want to look into your emissions laws. In AZ you can only swap in an engine with the same number of cylinders that was offered from the factory, make doesnt matter. For example, CJ7's in the 70's and early 80's had the 304 V8 option, so i can put a chevy v8 in my 79 if i want to (and plan to). If i had an 86 i would be SOL.

The same would hold true on you MJ and an 8, it never had the option.

Like i said, check your laws, but something to think about

.02

i have a 79 chevy v8 on propane on my XJ its registered in Pima county and passes emissions. well it failed the last sniff test my timing was all screwed up. But they look for a cat if it came with one though on propane you don't need one.. two years and no issues.

I'd hold out for a 87' and up. Reason being you can get one for cheap with the 4.0 and an AW-4 and 86's were only long beds. The short bed makes a better base for a trail rig.

You should be able to find one for around a grand. Why waste all the time and money converting a long bed with the wrong motor?

my 2 cents.