4.0L Jeep EFI Retrofit Feasible?

I was doing a Google search looking for EFI systems that could be used on the small block six and came across the 4.0 Liter six used in the early 90's (91 to 95 I believe) Jeep Cherokee.

Some companies are marketing this system as a bolt-in upgrade kit for the earlier 4.2L six used in the CJs and YJs. These kits include everything from the ECU, to the intake manifold, injectors, sensors, and wiring harness. This system is multiport, and I believe it is before OBD, and therefor a lot simpler.

With so many early 90's Jeep Cherokees occupying junk yards (sorry, auto recyclers), I wonder what the possibility would be of pulling one of these EFI systems and retrofitting it to a 200 or 250.

What do you all think?

the 250 would be a better fit as it's about the same CID
however, you'd need to completely fab up a way to mount the injectors to the log, as well as the throttle body, and you'd need to figure out how to get the spark signal synced up (i believe this would work http://fordsix.com/forum/viewtopic.php?t=53733 ), then you'd need to worry about sensors matching up

it would be possible, but it would take a lot of researching and fabbing

With all the fab work for the little 200 I dont see any advantage to starting with another system. You may get it to run using something similar in displacement but if everything else is not off the same engine and set up the same way I think you will still need to tune it. Now there are things like Megasquirt that can be configured to anything. There are also other systems that have some flexibility. I just dont see any advantage to stock ECU's anymore. As far as getting back to the 200 the first issue is getting holes in the right place for the injector bungs then getting them welded in. Next you have to build a custom fuel rail. It needs the holes drilled in it to match the angles of the injectors. They require a special bit to get the step to seal properly. Once you get that part done the rest is fairly easy with something like a megasquirt.

I got a good solution for you...

Why not just put the whole 4.0L engine in there and save yourself all the hassle of machining and modifying the 200...you gain the simplicity of the EFI that will all just bolt on and you get a bigger motor!...a no brain'r!

I would rather adapt a transmission cross member and motor mounts to simplify and justify doing the swap in the first place, then trying to find fitting adapters, modifying the dizzy, the log intake for injectors, fuel rail, sensors and all the other stuff related to doing a EFI swap...I had a YJ here for 3 days installing a lift kit and the motor looked like it would be an easy weekend swap...the sump is in the same location, the radiator hoses looked to be in the same shape and size...I was just amazed at how similar they both were...there are a lot of people out there yanking these out in favor for a V8 swap...or should be able to locate a roll over special.

I say simplify the swap and just concern yourself with motor mounts and cross member...after finding this thread I might just sell mine and go for the whole motor package myself as the 4.0 jeep motor too has a lot of aftermarket goodies and the intake come off.

See what you started, now you got my brain hurt 'n again

Now that's a bargain for a complete swap...$500 bucks is a steal for a engine and trans combo and since this owner is going diesel, I'm sure you could snag the whole ECM and harness as well...and it is a 2wd train.

http://nashville.craigslist.org/pts/1065073329.html

here are some 4.0 specs I found that may be a very convincing reason to do the whole swap.

Jeeps Kick Ass Engine - The History Of The 4.0L

Jeeps Kick Ass Engine History 4 Liter High Output

This model year reveals a better-flowing Power-Tech Six High Output version of the 4.0L. Changes are made to the cylinder-head design, the camshaft profile, and the block castings. The YJ makes 180hp and 220lb-ft of torque while the Cherokee's mill has 190hp and 232lb-ft of torque (variation in numbers is due to differences in design of the exhaust and air cleaner).

The 4.0L gets some upgrades, including lighter pistons, new cylinder-head casting (to improve the exhaust flow), a new two-piece thin-wall cast exhaust manifold (that replaced the one-piece, tubular style), and steel valve covers (again).

The block is tweaked so that the oil-filter mounting can be relocated, meaning the Grand Cherokee no longer needs an adapter.

This is the last model year for improvements to the 4.0L, which include new direct-mount accessory drive bosses, a thrust washer added to the camshaft, a new chain oiling system, and larger-diameter casting between lobes (to stiffen the camshaft in "bending" mode). Also, ribs are added to the rocker pedestals and holes are tapped for the new coil rail system in the cylinder head.

The 4.0L ends production. The TJ is the last application.

* '87 Cherokees and Comanches were the first to get the 4.0L.
* '91 YJ was next.
* '93 is when the Grand Cherokee got it.
* '97 was the first for the TJ.

Seriously, very impressive numbers for a 242ci engine...that's only a stock engine barely pushing 1hp per ci.

If I was going to do a non-Ford six cylinder swap, I'd look at the BMW 3.0L six.

IMHO, it's one of the better sixes out there. It came with carbs or EFI, and there is alot of performance upgrades for it.

Of course, I may be biased towards BMWs.

rocklord":3gn5s8b9 said:

If I was going to do a non-Ford six cylinder swap, I'd look at the BMW 3.0L six.

IMHO, it's one of the better sixes out there. It came with carbs or EFI, and there is alot of performance upgrades for it.

Of course, I may be biased towards BMWs.

Click to expand...

Me too...'course, I lived in Germany for almost 5 years. Soon as I'm out of debt this summer, I'm getting a 2003-2005 M3.

I will agree that the BMW is a nice motor, however I did own an older 80's BMW and will contest that part prices are out of this world expensive...that's how I would determine what to use....get a cost on replacement parts and go from there...good luck with your project.

I don't know how I missed this thread.
The 94 and older EFI system on the 4.0L was the Renix style. Which is very hard to find parts for and much more complicated then the 95 up style. When a Renix EFI dies, after about a week or so the owner is usaly wanting the newer deesign EFI system.

thought the 4.0 would be a great idea. Got one wating to go into my old jeep (fuel injection baby!). Compared the 4.0 and my 200 and it looks like it might fit with some slight mods, there is one thing though, the oil pan sump on the 4.0 or 258 for that matter, is at the rear of the engine, on the 200 and 250 its up front. So unless you can find a 4.0 with front sump it will not fit.

Then again, since the 258 and 4.0 are so much alike (4.0 is a newer version of the 258, just about the same block) maybe if you can find a AMC Eagle sedan / wagon (late 70s early 80 vintage) and see if it has a front sump oil pan, that may be the work around.

Zorm":2qib1m9e said:

thought the 4.0 would be a great idea. Got one wating to go into my old jeep (fuel injection baby!). Compared the 4.0 and my 200 and it looks like it might fit with some slight mods, there is one thing though, the oil pan sump on the 4.0 or 258 for that matter, is at the rear of the engine, on the 200 and 250 its up front. So unless you can find a 4.0 with front sump it will not fit.

Then again, since the 258 and 4.0 are so much alike (4.0 is a newer version of the 258, just about the same block) maybe if you can find a AMC Eagle sedan / wagon (late 70s early 80 vintage) and see if it has a front sump oil pan, that may be the work around.

Click to expand...

Even if one was never made factory a oil pan is just sheet metal it can be made to fit what ever you need.