smallblock/bigblock comanche?

[my86mj]

has anyone done it. i was looking at smallblocking a s10 and i thought wait. i like jeeps i have a comanche i could get another one and make it a monster. so has anyone put a smashing chevy v8 into a 2wd comanche? what engine did they use what transmission? any takers?

[jimoshel]

I once installed a bored and stroked 500CI Cadillac into a MJ. Kept the BA10 and D35. If I had only eased the clutch out instead of reving it to 6 grand and then dropping it I might have gone farther than 2 feet. The neighbor doesn't mind the trans&differential fluid all over the road but the shrapnel in the side of his house has him kind a p*ssed. :shake:

[my86mj]

what in gods name made you think a ba10 was a good idea

[Pete M]

what in god's name makes you think Jim is telling the truth? :rotf:

 

v8s have been done. be prepared to spend tons of money and fight cooling issues. :thumbsup:

[jimoshel]

Aw come on now Pete. Anyway i always thought BA stood for BadA**

[my86mj]

well i wouldnt use any stock plumbing but i was toying with the idea. sounds like a lot more fun than a stock motor with boost

[mpace6a]

I was considering a sbc for a while, since its a ton of work to make anything bigger than a 3.4 v6 fit. but i like diesels, so I'm gonna wait until i have everything together for a cummins 4bt. its more work to get in there, but ive seen it done. and therefore, i shall do it. who doesnt want 45+mpgs?

[cody4359]

viewtopic.php?f=7&t=34036

[my86mj]

hes not quite done yet. and isnt that a chrysler 318?

[Incommando]

hes not quite done yet. and isnt that a chrysler 318?

5.3L (327) late model GM.

[Zenobian_84]

Y'know, I was seriously thinking about this same question at work tonight (today? :dunno:). Although, it wasn't a Chebby motor I was thinking of putting in; it was an early model AMC 304.

 

I was mostly thinking about getting my grubby hands on a 304 and using it to tear down and rebuild in preparation for going to school next year.... but y'know. I think the 4 pistons already there in my truck could use another 4 sisters; if you catch my drift. :brows:

 

My only beef with the 304 is that the later models could barely keep up with my own 150. What a shame emissions crap will do to an engine...

[Incommando]

Y'know, I was seriously thinking about this same question at work tonight (today? :dunno:). Although, it wasn't a Chebby motor I was thinking of putting in; it was an early model AMC 304.

 

I was mostly thinking about getting my grubby hands on a 304 and using it to tear down and rebuild in preparation for going to school next year.... but y'know. I think the 4 pistons already there in my truck could use another 4 sisters; if you catch my drift. :brows:

 

My only beef with the 304 is that the later models could barely keep up with my own 150. What a shame emissions crap will do to an engine...

 

I would totally do a 360. They have the exact same external dimensions so you get 54 cubic inches for free. In stock form in any given year a 360 would get you 50-75 more horsepower and up to a 100 more foot pounds of torque than a 304 for the same buy-in cost. For me they are easier to find as well. Everybody does a SBC becuase they are cheap and easy... I hope they don't chose their wimmin by the same criteria.. :D The front distributor engines like the AMC or a SBF are often much easier to install because you can put the engine closer to the firewall. ( The 401 is a great motor and the same external size as the others but they are getting very pricey and you could easily match the stock 401 numbers by bolting performance goodies on the 360 and still be a ton of money ahead)

 

Although the horsepower ratings for the last couple of years of 304 were 130-ish your reasoning that the low HP rating makes it and the 150 equal falls into the age old trap of forgetting both torque numbers and power band. During its worst years the 304 had considerably more torque (220) than your I4's 130 foot pounds. As people only seem to understand horsepower numbers: would you consider a 130hp & a 220hp engine equal? Of course not. So why do you think a 130 ft/# engine is remotely the equal of a 220 ft/# engine? The 304 produced its peak numbers at a lower rpm as well so that it would be a much better engine in the real world. Horsepower is not the be-all and end-all of power ratings and IMHO is best used only for bragging rights. My '93 Dodge CTD only had 160 horsepower...do you really think that a 160 HP I4 could compete with it? Would a 160 HP Accord I4 even MOVE my CTD dually let alone tow a 12K trailer as well? Of course it would, they are both 160 horsepower.... :D The same principal applies to the 150 and even the worst years of 304.

[HKB3]

Still debating between doing a simple 2.5 to 4.0 swap or 2.5 to 5.3(L33) swap.

The LSx swap will only cost me slightly more then a 4.0.

4.0L h.o. 515lbs. 190h.p. 16-19mpg(on a good day)

 

5.3L vortec L33 425lbs. 310h.p. 16-19mpg in a jeep on 35s

 

Putting a LSx into a jeep is pretty common and economical these days, plenty of reading here:

http://www.pirate4x4.com/forum/showthread.php?t=735270

[Garvin]

If you're looking for a Chevy Gen I swap then look into my build thread (currently running a TBI long block with TPI fuel injection). I was running it carb'd on a few previous engines (I used to be a bit rough on these engines, calmed down a lot since then). Linked to page 3, about half way down is the current engine.

 

viewtopic.php?f=7&t=29562&start=30

[Eagle]

well i wouldnt use any stock plumbing but i was toying with the idea. sounds like a lot more fun than a stock motor with boost

It's not.

 

Pete isn't kidding about cooling issues.

[Garvin]

Cooling the engine actually isn't that hard, you won't cool that well on stock components though. I have a Cherokee CSF 3 core aluminum radiator and a little addition I did with a heater core and the 350 runs around 210 degrees at cruising speed and 180ish at idle on a 90 degree day. V8's aren't as hard as everyone says they are to cool, you just need to think outside of the box.

 

Another way to cool it is to swap to a WJ steering box and slap a much larger radiator in there. Wagoneer ones fit the older Jeeps ('84-'86) pretty well, forget what year I looked up when I was planning on doing that.

[Pete M]

I'm not saying the cooling issues can't be overcome, I'm saying that someone looking into a v8 conversion needs to expect to go all out. :yes: (and fwiw, others have installed big rads and still had issues)

[Zenobian_84]

Y'know, I was seriously thinking about this same question at work tonight (today? :dunno:). Although, it wasn't a Chebby motor I was thinking of putting in; it was an early model AMC 304.

 

I was mostly thinking about getting my grubby hands on a 304 and using it to tear down and rebuild in preparation for going to school next year.... but y'know. I think the 4 pistons already there in my truck could use another 4 sisters; if you catch my drift. :brows:

 

My only beef with the 304 is that the later models could barely keep up with my own 150. What a shame emissions crap will do to an engine...

 

I would totally do a 360. They have the exact same external dimensions so you get 54 cubic inches for free. In stock form in any given year a 360 would get you 50-75 more horsepower and up to a 100 more foot pounds of torque than a 304 for the same buy-in cost. For me they are easier to find as well. Everybody does a SBC becuase they are cheap and easy... I hope they don't chose their wimmin by the same criteria.. :D The front distributor engines like the AMC or a SBF are often much easier to install because you can put the engine closer to the firewall. ( The 401 is a great motor and the same external size as the others but they are getting very pricey and you could easily match the stock 401 numbers by bolting performance goodies on the 360 and still be a ton of money ahead)

 

Although the horsepower ratings for the last couple of years of 304 were 130-ish your reasoning that the low HP rating makes it and the 150 equal falls into the age old trap of forgetting both torque numbers and power band. During its worst years the 304 had considerably more torque (220) than your I4's 130 foot pounds. As people only seem to understand horsepower numbers: would you consider a 130hp & a 220hp engine equal? Of course not. So why do you think a 130 ft/# engine is remotely the equal of a 220 ft/# engine? The 304 produced its peak numbers at a lower rpm as well so that it would be a much better engine in the real world. Horsepower is not the be-all and end-all of power ratings and IMHO is best used only for bragging rights. My '93 Dodge CTD only had 160 horsepower...do you really think that a 160 HP I4 could compete with it? Would a 160 HP Accord I4 even MOVE my CTD dually let alone tow a 12K trailer as well? Of course it would, they are both 160 horsepower.... :D The same principal applies to the 150 and even the worst years of 304.

Sorry for the :hijack: But...

 

I totally understand that Torque will trump Horsepower ANY day of the week. That's why when I've been looking into the minute amount of additions to my 150, I look at what kind of Torque increase I'll gain, rather than horsepower. I was simply stating why most people frown upon the 304 and call it a $#!& motor. By no means is the 304 a cruddy motor like most people assume it is, based on CI size and horsepower outputs past '75; it served its purpose for what it was put in, and although it wasn't a beast like the 401, it was good for what it was.. It performed well enough in the CJs, and was relatively all around good motor. I just read about everyone trying to get rid of their 304 for a good 360, and it seems like such a waste of potential to me.

 

My reasoning behind the 304 against the 360, is that everyone does a 360; and yes, there's good reason for it (way more 360s left than 304s) but I'd rather be an oddball. If that makes any sense. I doubt I would put the 304 or the 360 into the MJ; but I always wanted to rebuild an old engine, and what better than one made by AMC?

 

Now if I could get my hands on a decent, EARLY Gen III TD 401... I'd have to reconsider dropping it into the MJ. :wrench: ;)

[HKB3]

4.0L h.o. 515lbs. 190h.p./220tq 16-19mpg(on a good day)

 

5.3L vortec L33 425lbs. 310h.p./335tq 16-19mpg in a jeep on 35s

Update edit

Besides that they look cool

 

[Eagle]

Y'know, I was seriously thinking about this same question at work tonight (today? :dunno:). Although, it wasn't a Chebby motor I was thinking of putting in; it was an early model AMC 304.

 

I was mostly thinking about getting my grubby hands on a 304 and using it to tear down and rebuild in preparation for going to school next year.... but y'know. I think the 4 pistons already there in my truck could use another 4 sisters; if you catch my drift. :brows:

 

My only beef with the 304 is that the later models could barely keep up with my own 150. What a shame emissions crap will do to an engine...

The 304 was completely emasculated compared to the 290 that preceded it, even in 1970 (which was the first year for the 304).

 

The good news is that the 360 (and the 390 and 401) are externally exactly the same engine, so it's no more (or less!) work to fit a 360 into an XJ or MJ than it is for a 304. I had a 360 2-barrel in my 1978 full-size Cherokee and it was a VERY strong engine. My brother also had a '78 Cherokee, but his had the 4-barrel version. It was a torque monster.

 

My reasoning behind the 304 against the 360, is that everyone does a 360; and yes, there's good reason for it (way more 360s left than 304s) but I'd rather be an oddball. If that makes any sense. I doubt I would put the 304 or the 360 into the MJ; but I always wanted to rebuild an old engine, and what better than one made by AMC?

What severely limits the 304 is the valves are too small. The 360, 390 and 401 have MUCH larger valves. I'd have to go find my copy of the old AMC "Go Fast Book" but my fuzzy recollection is you can't just bolt on 360 heads because the smaller cylinders won't allow the valves to open. Interference fit, and all that. But that doesn't mean you can't do a bunch of head work, porting and polishing, and perhaps fit in slightly oversized valves, to free up the airflow a bit. And torque at low RPM doesn't require as much air flow as high RPM horsepower anyway, so combine some head work with a good RV or torquer camshaft and you could be on your way.

[Garvin]

I'm not saying the cooling issues can't be overcome, I'm saying that someone looking into a v8 conversion needs to expect to go all out. :yes: (and fwiw, others have installed big rads and still had issues)

 

I'm not pointing fingers or throwing people under the bus here, was just putting my 2 cents in from my experience since I ran into this same issue. There's definitely more to it than just slapping in a larger radiator also. My setup isn't just the radiator and little addition, I also have stainless steel hoses (they actually dissipate a lot of the heat in the coolant also) and a high volume water pump. With everything said and done, I have about 5 gallons of coolant in my system (compared to a normal Jeeps 2-3).

 

Everyone is right though, it is not cheap. The main reason I went with a Chevy setup is because I found the Novak Adapter to mate an AX15 to the 350 as well as with everything I needed locally for less than just the adapter is new. If I were to do it again, I would have went with a Ford 351W. It's a lot easier and cheaper to slap a Ford engine in there since you can slap the ZR5 right behind the engine (the Ford 5 speed manual) without worrying about customizing the shifter as well as the transfer case is the correct side drop. It seems like the Chevy setup is far overdone and the Mopar setup is catching up fast.

 

If you do go the Chevy Gen 1 route, I can help you with advice on what I did since mine is also done to an '86 also.

 

What severely limits the 304 is the valves are too small. The 360, 390 and 401 have MUCH larger valves. I'd have to go find my copy of the old AMC "Go Fast Book" but my fuzzy recollection is you can't just bolt on 360 heads because the smaller cylinders won't allow the valves to open. Interference fit, and all that. But that doesn't mean you can't do a bunch of head work, porting and polishing, and perhaps fit in slightly oversized valves, to free up the airflow a bit. And torque at low RPM doesn't require as much air flow as high RPM horsepower anyway, so combine some head work with a good RV or torquer camshaft and you could be on your way.

 

I was actually going ask about the head swap but you covered that nicely. You are definitely correct, you want to figure out the power band you want to be in. I set mine up so the torque peaks around 3k and pulls hard off idle. I don't see any real reason why you would need high RPM horsepower in a Jeep unless you plan on racing it (Jeepspeed maybe?).

 

4.0L h.o. 515lbs. 190h.p./220tq 16-19mpg(on a good day)

 

5.3L vortec L33 425lbs. 310h.p./335tq 16-19mpg in a jeep on 35s

 

On the engine in my Comanche currently, I'm running about 16mpg but haven't had the Jeep running perfectly yet to really test it. This is also on one ton axles with 15/38.5 bias ply Ground Hawgs and 4.10 gears. I believe I've read that the Gen 1 engines weigh in around 560 lbs but I'm also running around 300hp and 350tq out of this thing. That is one clean L33 install though!

[COFFMAN]

4.0L h.o. 515lbs. 190h.p./220tq 16-19mpg(on a good day)

 

5.3L vortec L33 425lbs. 310h.p./335tq 16-19mpg in a jeep on 35s

Update edit

Besides that they look cool

 

 

Dose anyone know the link to this o so sexy build, would love to check it out, Thanks

[HKB3]

There is a build thread on the red XJ @ ls1tech somewhere(I took me a while to find and I forgot to save the URL)

 

Lot of great tech here:

http://www.naxja.net/forum/showthread.php?t=1007477

[jimoshel]

My 2 cents worth. I have probably done over 3 dozen engine swaps into Jeeps, the older FS models, not a MJ. I only did one Chevy. The first one. After that only used Ford or Buick, preferably Buick..Did do a couple Caddys. My reasoning is the distributor placement and weight. Found the FE Fords to be the easiest to do and readily available. And I am not a Ford man. Although I did have '57 Ford convertible once that I liked.

[carnuck]

I was planning on using an AMC 290 (or 304) that I have and an AX-15 in the longbox I was planning to extend the cab on. (too bad my body is buggered up and I''ll never get 1/4 of the work done I had planned)