1990 YJ AMC 258 swap for amc 360

[murray195]

For the passed couple months I've been weighing out my options for potential engine swaps for my YJ. My current set up is an AMC 258-TF999-NP231-D30-D35 (stock short of the fuel system).
For potential swaps, I was looking at these two places for mount kits:
http://www.advanceadapters.com/categories/engine-mount-kits/59/1990/0/13/0/0/0/0/
http://www.novak-adapt.com/knowledge/yj_87_95_swap.htm

For GM I was reading the following webpage among MANY others:
http://www.novak-adapt.com/knowledge/yj_87_95_swap.htm

For Ford I was reading the following webpage among once again, many others:
http://www.novak-adapt.com/knowledge/fsb_swap_yj_87-95.htm

And after reading up on mopar, I completely threw out that option.

As with pretty well any frankenstein swap, transmission, transfer case, and axles become the primary focus because you can weld up mounts and cut to fit to put the heart in  

With both GM and Ford, I discovered I'd be neck deep in adaptors, modified axles, etc. Everybody seems to say "Just throw a SBC 350 in that beast". And there reasons for it are usually parts availability, or heard about it being done, or they're red-necks who think the sbc 350 is the "cure-all" like that gray gold we call duct tape   All kidding aside, the Ford was looking like a better bang for my buck for a number of reasons.

But after taking a ride in my buddy's CJ with a AMC 360, I started reading up on them.
I understand there are a few issues with it such as parts availability, oil delivery,its external balancer, and exhaust. However nothing I read about it made GM or Ford more attractive.

Here's where I need some first hand experience, not speculation and not judgement. I need to know what info I'm missing before I go ahead with the 360 swap. From my research I've found the following:
-The 360 will bolt right up to the TF999
-The fuel pump is on the passenger side just like the 258, but the hardline may require "tweeking"
-If I get the motor from a FSJ, I'll need the engine side cast mounts for a CJ that was equiped with a 304 or 360
-My frame side mounts will work, but the passenger side needs to be elongated.
-The cheapest exhaust system solution is fender headers
-A triple-core rad with a separate transmission cooler off of an F-150 that had the towing package is necessary for low speed wheeling.
-The throttle is the same concept as the 258 (integrated kick-down) and very minor modifications may be required
-If desired, the fuel system can be upgraded to TPI from a late 80's, early 90's FSJ down the road.

So, if anybody has any advice or tricks they could pass on, please do so. And if I'm overlooking anything small or anything that could be a real hang-up please tell me about it. I want to have everything ready to go so it's a weekend swap (it's my daily as well as my toy).

My goal:

[cLAY]

I'm not to up on AMC V8 motors, what is TPI? Or did you mean TBI? I didn't think there were ANY fuel injection options for AMC V8s other than completly stand alone units like Holly Pro-injection. Personally I have a real hate for carbs and wouldn't do an engine swap unless it included fuel injection.

I did help a friend swap a 258 into a CJ that had a 360 many years ago. One thing I remeber is that the V8 setup had a brace that went under the motor from motor mount to mount that stiffened up the frame.

[cLAY]

Out of curiosity have you considered a 4.0 swap? A 4.0 with a cam would have comparable HP and torque numbers to a stock AMC 360 and be more reliable and get better mpg.

[murray195]

Yes, sorry cLAY I meant TBI. From my research, I found there was fuel injection for AMC in the latter years. It is the internet though so...you never know haha. I'm very comfortable with carbs and I was kind of shooting for a minimum electronics set-up. I'm not rock crawling and encountering insane inclines, so cut-out hasn't been an issue with the MC2100. I thought about doing the 4.0 swap, but I don't know. From what people have said and what I've read, it seems like quite a bit of work to make my 1990 no different than a 1991. I was focusing specifically on this write-up:
http://www.bc4x4.com/faqs/yj.cfm?cat=5&faqid=138
I've been working on hondas for 9 years, and its such a nice change not having to mess around with cps, tps, maps, vacuum, and so on and so fourth.
I hadn't heard anything about that brace, but it would make sense to weld something like that up with the torque increase and slight weight increase.
With a 360 with a 4bbl from the early 70's I'd be looking at 295HP (220)@4800 and a torque of 395 (535)@3000
The 4.0 would be 177-190HP and 225 for torque. I'm by no means trying to start any arguements, just trying to keep the swap simple and cheap while at the same time not leaving me wanting more  

[jkrubi]

    Not to sure I the amc is the same as a mopar block, but in the mopar world the 360 is an ok. But in my opion swapping in a engine that has low support ( ie: parts, performance upgrades) does not make sense. You can be waiting for weeks for the parts to come in, if you are going to swap an engine in swap something that there are lots of and parts are easy to get.  As well if something happens to the engine ( dies, hole in the block, etc) at least it's easy to get a new eng from the wreakers if it's somewhat common.
 
     In my old mopar (1966) the kick down linckage is different from a small block to a big block, and mine never kicked down right no matter what I did. Had to find a correct kickdown and problems went away.  It will be the little things that are specific to a jeep that will be hard to find or you will have to fab them up.

      Swapping in a different eng that lots of people do makes senses. There will be kits to help with the install so it could be done in a weekend, and most of the problems have been solved. If you don't want to mess with fuel injection a 302 is a 302. The kit would be the same, kind of like a 350 is a 350, a 318 is a 318.  The bottom ends are all the same from a carb to an inj eng at least all of the early ones, and it allows you to go to inj latter in if you so want. Plus there is lots of performance parts out for these engs.
 
   That's my 0.02 take it for what it's worth
     

[murray195]

Thank you for your input jkrubi, I appreciate it  . Just in case anybody was wondering, the only thing the AMC 360 and Mopar 360 have in common is the displacement. I dunno, the 360 just seemed like the most simple and practical swap with wagoneers and older cherokees becoming more common at PNP. If I wasn't doing it on my own I may be leaning towards the 302. Its just that by the time I add up adaptors, the time, and the money, I'd be better off selling my Yj and getting into a TJ or later YJ. My driveline is in excellent shape with only 160k on it, I was just hoping for a substantial upgrade with minimal downtime.

[hps4evr]

what about finding a good running 1991-1995 xj and swap all the parts and pieces in? good engine, aw4 auto trans, np231? full harness. easy to find xj's. remove the old 258 and keep the crank and rods for a future long rod 4.0L stroker. may come down to how much time you have to do the swap.

[murray195]

Ya, I was thinking about something like that before. As you say, it comes down to time. I mean, I figured if I got a damaged xj, pulled the drivetrain, and parted the rest out I could potentially have a nearly free drive-train right? I'd still need to track down a fuel tank from a 91-95 YJ or mess around with an inline pump. There are so many options out there, all have their upsides and all have their downsides  Is it wrong to go with less is more for a swap in regards to electrical, ECU, TCM, etc? Short of parts availability, I was convinced the 360 was the smart choice in my case... but nobody seems to think its all that great of an idea. I mean are there any wagoneer owners out there who wish they had a 4.0 EFI? I guess that would give me some guided direction. Thanks again for all the input so far guys! 

[cjsteve]

I've had a 360 in my cj for a few years.  Wiring will be simple moving from a 258 to a 360.  Most of the wiring will be the same.  A good running 360 will last a long time, plus it a torq monster.  I've seen a 360 with a mc 2100 idle laying on it's side.  They really do work good.  Only trouble I've had is keeping seals in it.  Rear main is a pain in my rear.  If you need any parts let me know, I've got lots of spare 360 stuff kicking around.

[murray195]

Awesome Steve! Are you running HEI or TFI or just stock ignition? And what diffs are you running? MC2100 or MC2150 or Carter? I've got a line on a 360 that I should be getting later on this month. Sorry for so many questions, but what trans are you using? I'll for sure be looking for fender headers, cj block side cast mounts, and potentially flex plate/torque converter.

[rangerdanger]

I run the 360/tf999/dana 300 combo in my CJ 7, the previous owner swapped out the 258 for the 360, everything went in smoothly, the nice thing was the tranny bolted right up so they only changed the motor mounts, added the brace between them, spliced the new wiring into the old stuff, and added dual exhaust. The AMC motor is ok power wise but I think I would rather have a chev small block for better availability of parts and more power. Another thing to watch out for is AMC motors aren't known to have the best oiling systems either.

[murray195]

Good to know rangerdanger. Yes the oiling is one thing I listed in the cons but apparently it can be addressed during the rebuild. GM is my cryptonite lol, I've never had luck with them. Between main bearings, rear main seals, output seal leaks on the trans, valve stem seals, rings... lets just say we just don't get along. And I'm kind of a maintenance freak!  The sbc obviously works for a lot of people, but for me it's a dark road to go down. Maybe the reason why there's so many parts available is because they know I'll be stopping at the parts store every second day just to keep em running lol!  Auto value and kingsway love me when I have anything GM...

[cLAY]

With a 360 with a 4bbl from the early 70's I'd be looking at 295HP (220)@4800 and a torque of 395 (535)@3000

Those are impressive numbers. However I had 1980 Grand Wagoneer with a 360(4bbl) and I can tell you it didn't have any where near that kind of power.

Are you planning to just swap it over or freshen it up and add some upgrades.

[murray195]

I plan on doing a full rebuild, getting my heads planed, and upgrading:
fuel pump (Rebuilt 9PSI)
intake http://www.dragtimes.com/parts/Edelbrock-Performer-RPM-Air-Gap-Intake-Manifold-7531_370481387769.html
ignition (HEI or TFI)

And of course making it look Purrrdy 

[cjsteve]

I run my 360 with a dui hei, high rise intake, holley truck avenger 670, and headders.  The power is pretty good, and it runs great off-road.