If You Were To Build A V8 Comanche, Which Version Would Work Best?

[yellaheep]

So, I'm on the hunt for my longbed MJ for the Dually project and while it may not happen immediately, the long term hopes/plans are for an LS engine swap.

 

If you were looking to drop in an LS engine into an MJ, would the '86 era trucks work better for this swap because of their limited AMC electronics? 

 

Or would it be better (or just not that much difference) to find an '87-'92?

 

Seems to me you'd have more electrical/electronic issues to work out with the later models, particularly the '91-'92 trucks.

 

I've never done these swaps before and from what research I've done to this point, the aftermarket caters to the LS swaps.  Several "easy install" wiring kits out there for the LS engines.  Novak Adaptors makes LS engine mounts for the MJ/XJ.  There are a few aftermarket radiator options out there as well.

 

I'm wondering if the front firewall of the '86 trucks would be better for the more traditional radiator install?  Rather than the wide and short radiator needed for the inline 6 engine trucks......

 

Were there any unibody/rear frame improvements done to the later MJ's?  Seems to me that I've heard that...... can't find anything concrete though......

 

Words of wisdom?

 

There sure seem to be a much more abundant supply of '86 trucks on the cheap out in my neck of the woods........ but my past experiences with the earlier trucks and their wiring and rust issues tends to make me shy away......

 

The other factor complicating my decision is that I have a nicely built Renix 4.7 stroker engine sitting around begging to be used.  Just seems to me the LS engine has the potential to be better for torque and reliability.

[Minuit]

I'm horribly underqualified to properly answer this, but I don't think the year would matter much, as I don't think you'll keep much of the original engine-related wiring with that sort of swap. That said, the firewall improvements made in 87 might make fitting a big engine in there easier or may not depending on the dimensions of the engine. The biggest question is obviously in the cooling department, but I don't know if the year would matter, as I don't think your typical V8 swap will work with the original radiator hardware anyway. Feel free to prove me wrong on any of the above. The newer models will tend to be in better shape and just be better vehicles in general, so there's also that to consider.

[FrankTheDog]

Read the Novak LS swap guide on their web site.

It really shouldn't matter what year you use as the only wiring you'll be using is a couple of the original engine management like keyed hot wire and starter signal.

Headlights and such aren't in with the engine harness.

Start with the cleanest shell you can find.

[buffalob]

you would have far more room on your patio for the LS engine, if a friend were to "store" that stroker for you

[yellaheep]

Does anyone else here strongly suspect that Bob wants my stroker?

 

:D

[mvusse]

The firewall mods done in the 87 and newer trucks were to fit the long inline 6 engine. I'm pretty sure an LS V8 is shorter than the 4.0 straight six, so I don't believe any changes in the engine bay would affect you. All the radiator stuff is bolt in and might need to be modified anyway, so that shouldn't make much difference. And since you'll need to replace most of the electronics under the hood I don't see much of a difference there either.

 

So I would start with the most rust free, dent free truck I could find regardless of year.

 

Be aware that most people with a V8 in a Comanche or Cherokee seem to have cooling issues because the nose of our vehicles was simply not designed for enough airflow to dissipate the heat generated by a V8.

[Minuit]

Does anyone else here strongly suspect that Bob wants my stroker?

 

:D

 

Just a little bit :rotfl2:

[buffalob]

Just tryin to help a brother out guys!

[shelbyluvv]

I used a 5.2 in my 86. I had to cut the front cross member out and bolt in a ZJ lower radiator support. My raditor is a custom 3 core unit with a big electic fan and custom aluminum shroud. The 86 is not much different than the 87+ trucks. You will need to use the 87+ hood latches or use hood pins like I did. The center hood latch will hit the top of the radiator.

[buffalob]

Last time I dropped a V8 into anything (that did not have one to begin with) was a 318 from a 69/70 fury into a 72 FJ40 landcruiser.

that would have been back in 1978, way old school compared to what you have in mind ,but knowing how skilled and resourceful you are it will all work out in the end, I am really looking forward to your project. If you need an extra hand (or comic relief)...let me know.

[jimoshel]

I solved the problem of not enough room in the engine compartment by mounting four P51 Mustang engines direct to the wheels. One engine per wheel.Got the synchronous worked on and they pulled pretty good on a straight line. Had a little trouble going around corners, The two inside engines wouldn't slow down while the two outside speeded up. Hard on tires and handling. Altho cooling was a problem, required a 150 gallon tank of glycol kept under the hood in the former engine compartment, and the placement of four radiators, the biggest problem was fuel. You just can't drive into any Loaf an Jug or Shell station and fill up with 500 gallons of 150 octane. Finally settled on the detuned version needing 100 octane. Also retained two of the 8 .50 cal Brownings in case I encountered any road rage. :doh:  :rotf:  :eek:

[Minuit]

Did you need to trim the fenders any? :dunno:

[Akula69]

Ah...better get up a good head of steam before triggering the 8 .50's - I hear they can really slow you down

 

I solved the problem of not enough room in the engine compartment by mounting four P51 Mustang engines direct to the wheels. One engine per wheel.Got the synchronous worked on and they pulled pretty good on a straight line. Had a little trouble going around corners, The two inside engines wouldn't slow down while the two outside speeded up. Hard on tires and handling. Altho cooling was a problem, required a 150 gallon tank of glycol kept under the hood in the former engine compartment, and the placement of four radiators, the biggest problem was fuel. You just can't drive into any Loaf an Jug or Shell station and fill up with 500 gallons of 150 octane. Finally settled on the detuned version needing 100 octane. Also retained two of the 8 .50 cal Brownings in case I encountered any road rage. :doh:  :rotf:  :eek:

[Crash]

Since the engine bay/front frame is essentially the same, I would consider checking out some LSx swap on the naxja.org forums. Frank Z and John D come to mind for this. 

 

I as well, plan on doing some sort of LSx swap. Unless I end up building something, which may happen down the road anyways, I really would like to start with a 6.0/6.2L truck engine, LSx car style intake (stock, or FAST if I can afford, there's a vendor on pirate that has some awesome, high clearance oil pans), 6L80 6 spd auto would be awesome as well, novak headers, engine mounts, possibly rad, etc. 

[1964dart]

If it was me I would look to use a small block ford=230/289/302 with a strocker kit. or go old school and use a for flat head ford = or a buick 230ci engine.I've done both in flat fenders jeeps, would fit and be the head turner nof the day.

[Keyav8r]

I cannot believe anyone would even suggest that Bob might have any ulterior motives in his selfless offer to store the stroker. I also felt the urge to reach out to a fellow member and offer what aid I could during what I'm sure may be a stressful time. It is obvious that the logistics would be much easier for Bob to help a friend out. However, I stand ready to step up and take on stewardship of the stroker if Bob should be unable to accept the burden.

[yellaheep]

If it was me I would look to use a small block ford=230/289/302 with a strocker kit. or go old school and use a for flat head ford = or a buick 230ci engine.I've done both in flat fenders jeeps, would fit and be the head turner nof the day.

Two huge problems with your suggestions..... As interesting as they may be......

 

1) Emissions. I'm guessing you don't have it where you live and I hate you for that.....:D

 

2) Ford. Not in my vocabulary. Never will be.

 

 

 

 

Oh and should I find that I can no longer care and provide for my stroker motor, I'll post up an adoption thread with the appropriate adoption application and process. :D

[jimoshel]

Not sure just how many engine swaps I've done over the years. Been a couple. One thing I've noticed tho. Seems the more planning and research the guy does, the easier and better running the end product will be. First thing is, is it going to be a 'toy' or a practical every day driver? If it's a toy then anything goes. If meant for a dd then reliability is the top requirement.

Some of the toys I've done was a Continental C90 into a model A frame. A 1938 Stutz Bearcat into a sawmill. and a 1958 Packard into a dune buggy. Have done the usual Chevy swaps into just about everything. Chevy's are practical, reliable, easily obtainable and heavy. In my personal, and humble opinion Ford and Buick are two of the best engines for a swap. Just as good as Chevy but 200 lbs lighter. I've had good luck, and results with buick, olds 215, the Buick V6 and 350, 400 and the Ford FE family. And I'm not a Ford man. The firsts swaps I did, I had to make everything, adapters, mounts, everything. Now you can just whip out the ol check book, or CC and buy what ever needed. A lot more convenient but not near as much fun or learning experience. One of the disadvantages of swapping anything into a MJ is it's strong point. Unibody. You have to be more careful of what you cut and weld. If you're going to do a MJ swap then there is plenty of info for your benefit. Find it and use it. CC is a good place to start.With the wide and varied back ground of the members it's not likely you're wanting to do something that hasn't already been done by some one here. Use the search function. Ask.

Note to Mods; I'm just rambling. Feel free to delete any or all of previous post. Jim

[huck731]

I'm looking at an ls3 motor, but I'm also going to run megasquirt so it will have a custom engine harness.

[1989 Eliminator]

I'm not sure what year but I have seen before that a 5.0L from a mustang will fit in a Comanche

[yellaheep]

I'm not sure what year but I have seen before that a 5.0L from a mustang will fit in a Comanche

 

 

No Ford engines or transmissions guys.  Nope, uh uh, no way.

[Tom Tom]

Ok I have a question. Why a ls1 ? My line of thinking would be old school no computer no major electrical problems. Something like a chevy 327 or 283

[mvusse]

Because of gazillion aftermarket support.

[JeepcoMJ]

The simplest answer I can provide is that any MJ will work.

 

The electronics really just don't matter, at least on 86-90. 91-92 you'd need an 86-90 gauge cluster and cable. You can completely remove everything in the engine bay except the battery wiring, headlight stuff, and wires that power everything for lighting and dash related and starter relay wires.

 

You can use the gauge cluster and all associated sensors (h20 temp, oil pressure), tie in the volt meter again, and tie in the tach with a pulse meter adapter (if necessary) to keep it working.

 

I would just go with an LS motor. The honest opinion around my place is that since everyone does them, they're nothing special. But putting a windsor or cleveland in would be a travesty, and while logical, and AMC v8 would be cool but is so outdated it's not worthwhile for something you want to actually use.

 

 

For me, it would be between an LS or a ford 5.0....I'd probably pick the 5.0 since it's not as common of a swap and the aftermarket support is at least as good as chevy.

[yellaheep]

Ok I have a question. Why a ls1 ? My line of thinking would be old school no computer no major electrical problems. Something like a chevy 327 or 283

 

 

LOL....... clearly you haven't read this entire thread. 

 

Emissions.  It'll be required to have an evap canister, cat converter(s), possibly an EGR valve...... that kinda thing.  If the original truck had it, the modified version has to have it as well.

 

Secondly, carbureators are the suck.  Especially out here where elevation changes are common just driving across the state.

 

The diesel engine really turns me off in such a small truck.  The noise in particular.  Those 4BT Cummins engins sound like a friggin' farm tractor and while torque monsters, move the truck like a turtle for daily driving.  No thanks.

 

A nice, powerful fuel injected V8 with an overdrive transmission........ :thumbsup: