1985 XJ V8 swap ?'s and a few more..

Well this is my first post here so let me start off by introducing myself. I'm Steve. I've been on the hunt for a good trail rig for a while and last weekend I found an '85 2-dr XJ in really good physical condition in a guys backyard with a blown engine. Here's the info I have so far.....1985 Cherokee 4x4, 2.8l V6, Automatic, White w/ Tan vinyl interior and from the faded paint on the doors it seems at one time it was a Core of Engineers truck. Right now it's riding on 15x10 Outlaws and 33x12.5 At's which don't fit to well without any lift. LOL but it does roll which is all he wanted it to do. I offerred him $350 cash on the spot but he said he was looking for more like $500 so I asked him to hold it till later this week when I could come back for a closer inspection and possibly make him a better offer..he agreed. So on to the questions.

I've been told it should have a Puegot tranny in it with either an NP231 or 207 T-case...what's the easiest way to identify these? What should I look for as far as problems without being able to drive it? Any known issues with them?
As far as the engine goes I have been searching online and found quite a few XJ's with SBC 350/700R4 combo's but have had no luck getting in touch with the owners to find out any info. I have a 355/TH350 combo near complete sitting in my garage with Vortec heads, JE pistons, Edelbrock perf. intake, 4brl 600 Edelbrock carb., HEI ign. etc. all it needs is a crank kit to freshen up the bottom end and a few accesories. What all is it going to take to get the small block in there? i'm guessing at least it will need Custom D-shafts, motormounts and crossmembers....right? I've heard you can use the 2.8l S-10 V8 swap motormounts from Advance adapters as well as get the other stuff needed from them. Is that correct? Is it neccesary to get that stuff from them or are they fairly easily fabbed up? Is the Th350 tranny even worth using or would it be simpler/better to just get a 700R4 out of a 4x4 and use it. What about mating up the T-case...what's it gonna take?

Thanks for any help you all can offer. Sorry about all the questions but I'm trying to get some answers fairly quickly before the truck disappears.

Use the search feature...there is quite a lot of info available...the job would be quite a bit easier if the XJ is '88 or newer due to the "short" engine bay in the '85...but then again if a smallblock can be stuffed into a "Sami" one can be stuffed into a '85 XJ....

The questions about the existing drive train...the auto tranny is a torqueflite A-904...the Transfer case is a NP-207 the front axle is D30 high pinion and the rear is a D35.

Pardon me if i'm out of line, but if I were you...I would stick in a salvage yard 3.4 from a camaro and work on the suspension and drivetrain before I considered adding a bunch of power...cause all you will do with a healthy smallblock in the truck at this point is destroy parts...

wish I had an old Junker XJ to toy with. My buddy keeps trying to give me either his 351 Windsor or the 460 he's punching out. I'm all for FORD power but both of those motors would make it stupid fast. Man, I'm going to sleep right now to dream about this stuff.

85 V6 auto will be a 904, tcase if it has a full time selection ("Selec-Trac") will be a 228/229 and a non disco d30 in front, or if it only has PT then it's a 207 "Command-Trac" and a disco d30.
I agree that a 3.4 is a better option unless you plan on throwing gobs of money at it. Mine perfoms on par or slightly better than any 4.0 I've ever driven.
If it is a Selec-Trac set up then really you have a good starting point - non disco front, no slip yoke (unlike everthing else that would need a SYE).... drop a 3.4 in it, throw a 4" lift on it & hack the fenders a little and wheel the snot out of it till it breaks and upgrade things as they break.
Novak http://www.novak-adapt.com/ has done a few SBC into XJ conversions and can help you out in deciding how to do it, though.
I'm sure the 207 wouldn't last long behind a SBC... the 228/229 should though as AMC used them in the SJ's behind their 360.
The axles would not hold up well without some serious beefing up, and actually it'd probably be cheaper to swap in some d44's
Mike B.

Hey "1986xj", I have an '85 in which I plan to throw in a 3.4 in out of a camaro in the next month. Do you have any upgrades as far as the engine goes? Exhaust (if so, does it sound deep, or is it ricer-ish)? K&N? Are you happy with the engine? Any help would be great. Thanks!

85Chief said:

Hey "1986xj", I have an '85 in which I plan to throw in a 3.4 in out of a camaro in the next month. Do you have any upgrades as far as the engine goes? Exhaust (if so, does it sound deep, or is it ricer-ish)? K&N? Are you happy with the engine? Any help would be great. Thanks!

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Only upgrade is the weber carb and K&N air filter.... huge improvement over the POS rochester. Muffler is a decent sized stainless one that was put on by the PO (don't remember brand) but it's pretty quiet inside and I've never had anyone run it past me a wot so I could hear what it sounds like from outside. A V6 has a different sound, the OF 225 running through headers and flowmasters in my CJ sounds like an old 8N at idle and like nothing else I've ever heard at WOT. I did see an 85XJ today that sounded really good but I didn't go crawl under it to see what muffler was on it.
Mike B.

i have an 86 with 4.3 chevy. it is done with AA kit when i got it but i looked the kits up & AA did not make a kit for a sbc in those years because of the fire wall & radiator.
1986xj what weber do you have on yours? what kind on mileage are you getting? tony

It's a 38 DGES (kit part# K490), I've got it tuned in pretty close but I think I need to go one size bigger on the idle jets, to make up for the added displacement of the 3.4.
Mileage, hmmm not real sure at present, did check it a while back and averaged 17 with mixed driving. That was before I had it dialed in so I suspect it is better now. I have 460's in the 2 work trucks I use the most so I tend to just ignore mileage for the most part :dunce:
Mike B.

I fired up my small block chevy in my 85xj today for the first time.There is nothing like the sound of a healthy v8 coming from a vehicle that was never offered with one.I modified the stock v6 motor mounts and made them work in the stock location.I ordered a set of headman headers for yj v8 conversion and had to do some modifications to make them fit.But i really wanted headers on the engine.I am working out the radiator issues now.Which is kind of a pain in the a$$.The steering box makes it tough to get any thing between the frame rails.I'm looking at moving the crossmember in front of the steering box forward which should allow me enough room to slide a smaller cross flow radiator in front of the steering box and between the frame rails.I will try and get some pics posted soon.I do agree with upgrading the axles which i already have a 9 inch for the rear and a 44 for the front.There is some work involved and you need some fab skills, but considering the power the 2.8 had with 33's it is definately worth it.

Most of what has been said here is right. You can swap your fenders and radiator support for one from a newer model to get more room.
I am running an LT1/700r4 in my xj, soon it is getting an LS1. So many of the problems have been worked out that it is a lot easier than when I did it 6 yrs ago.
Shoot me a pm or email and I'll send some info.
Dustin
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