XJ V8 conversion

[LT1XJ]

One of the problems with the AW-4 is all the electronics and adapting them to a different motor. I personally don't like the AW-4, but willingly admit that I have toasted a 700r4. I still like the lack of electronics. LT1's and LS1's are swapped so much these days that conversion parts are easy to come by. An LT1 fits in a cherokee, actually better than it fits in camaros and firebirds. I don't know that I would spend the time messing with a 305, it seems to me that if you are going to get into something like an engine swap, it would be wise to spend a little more coin on the 350.
With the effeciency of fuel injected engines, I just can't see putting a carbed engine in an XJ, but that is just my opinion. I don't have anything against carburetors, that is what is in my GW. I put the LT1 in my XJ five years ago and there were very few v8 XJ's around then. Now, a search on ebay will return two or three. SO as this happens, conversion parts become readily available. I think the new LS1 is going to be a tighter fit compared to the LT1 in my XJ now, but I don't forsee any problems.
Dustin

 

[5-90]

If you gear right, you could avoid the whole debate and use a THM350 or THM400 - both are better than the 700R4, I think. Or, perhaps convert to a stick and forget the slushbox entirely!

On the subject of engine swaps, I'd probably forego the LT1 in favour of the SBChevvy 383 (350 +.030, 400ci Crank) as it offers better low-end power than most other SBChevvy combos - and that's what you want in a truck. It is this very idea that makes me shy away from using a regular pax car engine in an XJ - set up for a light truck, you will get better use out of it and it will be more useful to you. I've put 383's in a few trucks with great results.

BTW - The ZJ V8 is actually the ChryCo 318 (5.2l) - by the time the ZJ hit the streets, the 304 had been out of production for some time. Pity - I always did like AMC iron - they always seemed to put a little more thought into their work. A wholly underrated company, IMHO.

5-90

 

[LT1XJ]

As to the 2002 grand, it should be a 4.7. It maybe a HO, but a 4.7. They are loosely based on the hemi design.
As to the 383, I agree a good motor, probably whta my LT1 will become before it makes its way into the MJ. However, virtually any chevy 350 can be stroked to a 383.
As to the 700r4, I really like having an overdrive, but you could get by with A T350 or t400. Or a 4L80E, but $$$
Dustin

 

[dellstopjeep]

one last question....i promise, what is the general cost to change gear ratios to 4.56 doin it yourself, or having a mechanice do it? thanks.

 

[xjfanatc]

I also have toyed with the idea of A V-8 conversion in my 86, But this was due to the wonderous, powerful, and very reliable (I am sorry meant to say very non powerful, unreliable P.O.S.) 2.8 that is in it. I figured I need to swap in something different because it will not take the beating. Yet to may dumb@ss ideas I am piecing yet the third motor back together to try and limp it around for a little longer until I find the donor 3.4 that I finally decided to run. The V-8 conversion will be alot of work and I still plan this set-up for my 87 2WD that I have (figured what could be a better tow rig than another xj). Either way you go your looking into alot of work. I have never had the pleasure of running the I-6 in any of my three xj's but I assure you it will be in my next purchased one. I understand they are a very reliable motor, even though I have never ran one I would suggest rebuilding the one you have and build the way you want it. Just my .02

 

[Ghost]

mcconnaughey,
Z and M conversions specialises in Ford 5.0 swaps into Jeeps. Look here :wave: I'm not going to do it to my 84 but I will eventually do 5.0 to an XJ.

 

[Wallyman]

4-give me 4 going japanese here,as i am an avid american vehicle buyer.HOWEVER, as i understand it, the AW4 was used n the Supra also.Now i just thoght of this so i didnt have time 2 look up specs, but it also used an I6, mabye a possibility?

 

[5-90]

Correct - The AW4 was originally found in the Toyota Supra (Turbocharged Celica I6), RWD Van, and pickup truck. AMC got hold of it and improved the clutches a bit for the XJ/MJ, as well as some valve body changes.

The AW4 has (I've read) held its own behind some decent small blocks, and has been compared favourably to the THM700R4 (General Motors 4-speed auto with reverse valve body.) I know the clutches in the AW4 are heaver, and it's survived worse abuse than I've delivered to 700R4's. The only way to really do better is a competent race-built THM700R4, or going with a THM350 or THM400 (and I prefer the AW4, it's a simpler box - if you ask me.)

If I was going to do a Ford engine, it would be a 289V8 or 300I6 (none of their other engines are worth a damn, IMHO. Besides, I don't trust a Ford I didn't build...)

I'm also wondering about the viability of the Mopar 346V8 Hemi swap, or potentially a revival of the 383 sixpack.

And then there's the 383V8 Bowtie Stroker, one of the best damn engines going!

However, I have yet to run across an engine block with the raw durability of the AMC258/242, except for the old Mopar Hemi "Mountain" motors from the 60's-70's. Alloys just suck these days...

5-90

 

[red87cherokee]

wouldn't lowering my gearing also mower my mpg??

It depends.

I swapped my stock 3.07 gearing for 4.88's in anticipation of installing some 35's I have in storage. But the tire swap won't happen until spring - so for a few months I have been driving on 31's (actually, right now I'm running my old 235/75R15's studded snow tires which I installed a few weeks back). With a corrected speedometer, my mileage improved since I'm in a better RPM range for the engine (with the 31's, I haven't checked it with the 235's).

Incidently, I have an '87 and my engine has something over 200,000 miles . . . but, my XJ has a manual tranny. With the 3.07's and 31's, I could use 1st through 4th gear (and 5th on downhills, only). Now, with the 4.88's and 31's, 1st gear is only used off-highway as a granny gear and I use 2nd through 5th in town and on the highway. Even so, it is much "happier" in all driving situations.

I can't tell you what the results would be with an auto, however. This is the best (also, most expensive) modification I have made. Even if I never get around to installing the 35's, I'll be happy with the improvement.

EDIT

The cost for regearing with all new components, installation, and lockers (Lockright front, Detroit rear) was just under $2,000 in the most reputable shop in this area.

 

[aspera]

4-give me 4 going japanese here,as i am an avid american vehicle buyer.HOWEVER, as i understand it, the AW4 was used n the Supra also.Now i just thoght of this so i didnt have time 2 look up specs, but it also used an I6, mabye a possibility?

7MGTE or 2JZGTE? If so, the turbo downpipe would dump straight towards the stock XJ cat! Excellent! No more hot foot. That would be an awesome engine for a Jeep.
http://www.toysport.com/Technical Information/spec_sheet.htm
Now I'm wondering what Toyota engines will bolt up. Will a 3SGTE work (with a RWD block)? Will a V6 out of a truck work? Tundra V8 or Lexus V8? How about a V12 from Japanese Toyota Century?

 

[aspera]

http://www.bulkpart.com/vehicle.html#TOYOTA

The Supra turbo shows as an A341E, while the N/A Supra is an A340E. The A340E looks like it was widely used (Tacoma, etc). I also found a Volvo thread trying to figure out if their autos were the same. A Volvo with a turbo Supra engine would be pretty sweet. Can you say sleeper? :thumbup:

Yep. The site lists both A340 and A341 for some Volvos. The A341 seems to have been used in higher torque applications. Six cylinder Toyotas and Lexus models used the A340, while V8 Lexus and Supra Turbos used the A341.

All of the I6 Jeeps show to be (A340F). Mitsubishi Montero (A340F). Toyota 4Runners, Previas, and Tacomas (A340F).

 

[aspera]

http://www.lextreme.com/pics/A340Diagrams.pdf

I found this cool exploded diagram of the Lexus LS400's A340. Does it look like a Jeep tranny?

 

[Tommy_Harrell]

AA has bolt in engine mounts, uses the 3 holes of the factory mounts on each side. AA also says it will clear the hood unless you use TBI, but it seams kinda close with a carb. I have just started on a 350 MJ (4bolt main, SM465, NP205, 14bolt FF rear and searching for front D60) on a 37" or 38"

HPI_Jeep posted some pics over on JU for me, will try to find them tomarow

Tommy

here is the thread
http://www.jeepsunlimited.com/forums/showthread.php?s=&threadid=545352
Still have lots of work to do (motor not rebuilt, MJ still 2wd, no clutch pedal ect...)

 

[Eagle]

wouldn't lowering my gearing also mower my mpg??

With an automatic and stock gears and tires, the engine is turning 2200 RPM at 65 MPH. That's already below the torque peak of the engine. Jump up to significantly larger tires and the RPMs drop to far below the torque peak. You'll gain both power and economy by re-gearing to get the engine back into the sweet part of the power curve at highway speed.