where do you guys stand on this idea?

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magnumdust

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I'm gonna bet this will start a pointless argument, but it was on my mind today. Which is the idea of taking a slant six A-body and swapping in a jeep 4.0 to do a 6cyl build. Arguably the 4.0 is a mopar engine, well more of a mopar/amc hybrid. But still close enough.

There are strokers/superchargers/turbo info/etc for the 4.0 and the important bit, its already fuel injected with a decent fuel injection.

Then again, would it even fit given that its not a slant mount orientation?
 
You can do it, its just all about time and money.
 
Neat idea, I think before I spent too much time on it I'd get the dimensions on the 4.0 to make sure it would even fit vertically. 4.0 only translates to 244 cubic inches, so its not all that much bigger than a 225.

If it can fit, then it'd be a pretty cool set up. Only thing will be that you'll be fabricating all of your parts- engine mounts, transmission mounts, etc. There won't be any vehicle specific parts for you, so even some of the aftermarket 4.0 stuff may not fit because its in an A-body and not a jeep (especially turbo/supercharger stuff, could be plumbing issues).

There are a decent amount of turbocharged /6's out there already, so lots of info on how to do that.

Really just comes down to what you want to take on. Turbocharging and fuel injection on a /6 has been done, you'd be adapting aftermarket stuff onto the /6. Putting a 4.0 Jeep 6 cylinder into an A-body would pretty much put you out on your own, with the possibility of needing some pretty serious fabrication work.
 
72bluNblu said:
Neat idea, I think before I spent too much time on it I'd get the dimensions on the 4.0 to make sure it would even fit vertically. 4.0 only translates to 244 cubic inches, so its not all that much bigger than a 225.

If it can fit, then it'd be a pretty cool set up. Only thing will be that you'll be fabricating all of your parts- engine mounts, transmission mounts, etc. There won't be any vehicle specific parts for you, so even the aftermarket 4.0 stuff may not fit because its in an A-body and not a jeep.

There are a decent amount of turbocharged /6's out there already, so lots of info on how to do that.

Really just comes down to what you want to take on. Turbocharging and fuel injection on a /6 has been done, you'd be adapting aftermarket stuff onto the /6. Putting a 4.0 Jeep 6 cylinder into an A-body would pretty much put you out on your own, with the possibility of needing some pretty serious fabrication work.
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By chance i found a short lived thread on this topic a few minutes ago on slantsix.org. It looks like the engine has similar dimensions as the old hemi-6 from Australia. So i guess in theory size wise it fits.

No clue on engine mounts *yet*. I'll just have to find some slant six engine mount pics/k-frame pics and see how it looks compared to the 6cyl jeep my dad has.

And yeah its not a huge diff. size wise. i think the biggest slant is a 3.5, but just the notion of the modern engine(no crap cast pistons/70s era tolerances) would be nice. Even if the power difference is likely minimal, there's a case to be made for drivability

tranny mount good be very easy. Just get an AMC 904/999.

Of course this is all in what if land. I'm gonna ask this local guy about what looks like a mopar in his backyard. Which could turn out to be nothing or a V8 car.
 
OR you could pull out one of those new 3.6L Pentastar V6 motors out of a wreck Challengers (they make 305hp (6350RPM with 6400 Redline RPM)/268lb-ft (at 4,800RPM)). However if you can wait a couple of years, this motor is being planned to put out so big numbers "Twin and single turbocharged variants are planned for 2014. These engines are projected to produce around 420 and 370 horsepower respectively. Direct injection is also planned."

Just something to think about.
 
That'd be cool, but there are so many more unknown variables IMO.

And um, wha? so would that be no more V8? It feels like that move would put dodge in the same spot as hyundai with their genesis coupe. The much cheaper turbo model is better car to build on.
 
magnumdust said:
That'd be cool, but there are so many more unknown variables IMO.

And um, wha? so would that be no more V8? It feels like that move would put dodge in the same spot as hyundai with their genesis coupe. The much cheaper turbo model is better car to build on.
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Have no idea, but with that next step in that piss poor CAFE standard, they gotta do something. Besides, a turbo 6 can make good power and still get decent mileage (as long as its EFI) think the Buick GNX or Nissan GTR
 
There is a stroker kit for the 4.0 that makes it IIRC 268-270 CID, and a T5 manual trans from a Mustang is a bolt on! ...also easy late 4.0 EFI and upgrade head!

I found this stuff out while researching the possibility of purchasing a 67 AMC rebel wagon with a factory 4 speed (and the 4.0's pre-cursor, a 258 ).
 
I think this idea is defiantly worth investigating. If it looks like it will shoe horn in there the 4.0 is a great motor and there's everything under the sun for them in the aftermarket. I it would be a cool build with a 5 speed.

JMO, good luck! Its probably been done by someone... maybe...
 
Anything is possible. Sounds like a good idea. You'll need some good fabricating skills to pull it off though.
 
I saw the words "pointless argument" and thought "Hell, I'm in".
I kinda like the idea. Besides the easy 5 speed upgrade, there should be plenty of donor engines out there. Jeep guys love them things and if I recall correctly, there is one member here racing one and another had posted a thread on stroking one a while back. So there is info starting right here in the family.
 
I think it deserves some further investigation also. The trick will be getting it low enough in the K member as to not require a cowl hood:D.
 
Neat idea, but you would probably have to cut the hood. I understand the slant design was to give a low hood-line, with the added benefit of long intake runners. Not sure why they used it in trucks, which can take a tall engine, other than it was already there. Is the 4.0L an overhead cam? If so, the head sits way above the block.

Don't underestimate the difficulty of making custom brackets and wire harnesses. Those can be the show stoppers. Fitting everything in is a major effort. I am sure the manufacturers spend many man-hours on each new design. Today they can use CAD, and they sure pack it in tight. Other threads have contemplated fitting other modern engine into a Dart, like the Mopar 2.4L or 3.8L, but "too tall" is the usual conclusion.
 
The aussie 245 and 265 will fit under the bonnet (hood :p) of an A body, so the 4.0 Jeep should.( The black '70 Valiant in my avatar has a 265, and the same hood height as a 69 Dart)
I can see lots of good points for it, most have been mentioned.
A turbo, EFI, 5 speed, 4.0 in a '67 -'69 Barracuda would be quick, fast, and make jaws drop.
And, if you were good with your hands, not too expensive.
 
a couple pics of one of my 96 4.0 litre HO jeep engines. great motors, i have seen them go 350,000 plus miles. they are TALL motors. you would need the entire engine harness, the computer and engine management systems and you would have to work the AW4 trans in there which is also a large trans. im sure it can be done, though ive never seen a swap into an A body
 

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I like the idea,....Lots of work though,....I believe the Jeep 4.0 used to be the 258 C.I.D.,.....been around since 58,....the one in my Fire Dept. responder rig has proven to be bullitproof for 150k miles,...runs like a raped ape,...lots of low end grunt,(torque)...never any engine repairs cept for occasional tune-ups and O2 sensor's,...gets about 18-20 mpg, but mine is a 2wd with a 5 speed and an 8 1/4 limited slip...thought about takin it to the strip just to see how it would do...also there is a ton of speedy/performance parts available...
 
jaimus said:
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I like the idea,....Lots of work though,....I believe the Jeep 4.0 used to be the 258 C.I.D.,.....been around since 58,....the one in my Fire Dept. responder rig has proven to be bullitproof for 150k miles,...runs like a raped ape,...lots of low end grunt,(torque)...never any engine repairs cept for occasional tune-ups and O2 sensor's,...gets about 18-20 mpg, but mine is a 2wd with a 5 speed and an 8 1/4 limited slip...thought about takin it to the strip just to see how it would do...also there is a ton of speedy/performance parts available...
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They're similar engines(258/4.0), but the 258 is a bit of a boat anchor for an engine. The highest output version was like 112hp. lol

Unfortunately i didnt see the guy this morning when i went jogging, but i'm pretty confident its a duster now. Maybe tomorrow.
 
Hood clearance might be a major hurdle, along with length. The 4.0 is in many ways a more modern engine than the /6. The 4.0 is a 1986 redesign of a 1964 engine, while the /6 is a 1959 design. The 4.0 has a 7-main crank and a much shorter stroke resulting in a more durable bottom end at high RPM. The stock 4.0 head is no flow monster, but responds to porting well.

The best year group for a swap would be a 2000-2001, stay away from 2005-2006 (the OPDA was junk). If it were me, I would use a Megasquirt instead of the factory CPU which is really not performance mod friendly.

Transmission wise, there were various 3 and 4 speed 904 derivatives which could be mixed and matched.
 
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