I am putting a Chevy 350 (dont know the year yet but looking for TBI) with a 700R4 trany and keeping my NP231 transfer case into my 1989 Jeep YJ. I have a 2.5l with a AX-5 right now.

My questions are:

1)Are there any good guides out there for this, I am fairly skilled with a wrench being an Aircraft Mech on Navy Jets so I can figure about anything out with a book.

2)What year engine should I use, I am trying to aviod a carb so I need something with TBI or better. I dont want a whole lot of electronics either and I can not afford to spend a fortune on the engine ($1,500-$2,000).

3)Anyone know of a good radiator that will bolt in to my jeep that can suport a 350, I also would like a seperate trany cooler and an electric fan.

4)Does anyone have any experience with Novak I am going through them to get my trany to transfer case adapter ($470), is there another company that my be cheaper yet just as good.

5)Besides having to modify my driveshaft lenghts is there any other expenses that I may not yet for see and that I need to look into. I most likely will not be getting an engine with a harness so I will have to modify my own or by a wireing kit. I know that I need new engine mounts also.

Well any help that some one can give me with be a huge help, I am currently down in Central Cali' so if some one is in the area and has done one before please let me know.  

The transfer case and D30/D35 axles from a 4 banger Wrangler will NOT stand up to that engine. Further, with a 700R4 in there, your rear driveshaft is going to be like 12 inches long. See a problem with that?
You need to take a step back and rethink this. If you're going to swap in a 350, then you need to swap the ENTIRE driveline. Engine, transmission, transfer case and axles. You're not going to be able to just change the length ofthe driveshafts either. The rear shaft in my '89 is 15" long. I used a TH350 for the shorter length. You will need a CV shaft, clearanced for flex, from someplace like Tom Woods. You can get a radiator from BeCool. B&M makes a great tranny cooler with a built in fan. For the engine, get whatever longblock makes you happen, and bolt on a Holey Projection TBI EFI system. Comes with the computer and wiring.  

You could install a 4.3 V6 which is about 5 inches shorter (a 350 with two cylinders removed) which means you could move it forward to give you more rear drive shaft room. As I recall a 700R4 is about 23 inches long from engine to tcase flange. If you use a adapter to mate to 231, you are going to add a few inches to this. I would suggest that you forget about using 231 (which as Dirty_Dog said is weak for a 350 anyway and marginal to maybe okay for a 4.3) and use a Tcase that bolts right to 700R4 without a adapter. Stock axles will live for a while with 4.3 and reasonable tires sizes but with 350 you are playing with fire. Also for what it is worth, a 4.3 is a very big upgrade from a 2.5 power wise.  

I was told by Novak that the Transfer case will hold up just fine and they do this for a living. They also said that the Dana will hold for a while unless I go and do something "Stupid". As for the it being to long the adaptor kit is only 1.1" long which comes out to a total length of 24.6" which is the equivalent to a 18.1" manual transmission so no the lenght is not an issue, if it was then why do so many people put a 350 in the Jeep.

I have been looking at getting a Suburban for about $1000 and putting all of the parts out of it into my Jeep, does anyone know what year I should look for and how much of a headache will putting new axles on the Jeep be.  

I am sold on the Chevy 350 and the 700R4 trany, the only real questions are if I can just buy a whole Chevy (say a Subruban down here in Cali for about $1000 dollars cause it dont pass emissions) and take all of the drive train and put it on my Jeep if anyone has done this please let me know. I am willing to upgrade my axles but like I said I have a limited budget of about $6000 and the Chevy would take $1000 of that.  

I still would not use NP231. You will be putting about 3 times the peak torque through it and that is too much for that case. When Dodge used a 231 with a V8 is some midsized trucks they used a different 231 that had 6 gears in planetary vs 3 like yours and a few other beef ups. (actually they basically used the reduction unit from a 241 in that model) If you are going through all this trouble, dump the 231 too. Also Novak is not going to buy your case if it fails nor could they sell adaptor if it was not "fine". Not knocking Novak but there is a reason that the do not use 231's in big trucks with V8's when they build them new.  

Not much point in asking for advise if you're going to ignore it, is there?
Novak is looking to make a sale. They're don't care if your axles break five minutes after you fire the engine for the first time. The only thing that might keep your axles from breaking is the NP231. It might break first. When they said the axles would hold unless you did something stupid, the something stupid they had in mind was actually engaging the transmission.
If you're buying a donor vehicle, buy one that is 4WD and swap everything.
It's not a difficult build, assuming you've got a stick welder and know how to use it.  

Dirty_Dog:
Not much point in asking for advise if you're going to ignore it, is there?
Novak is looking to make a sale. They're don't care if your axles break five minutes after you fire the engine for the first time. The only thing that might keep your axles from breaking is the NP231. It might break first. When they said the axles would hold unless you did something stupid, the something stupid they had in mind was actually engaging the transmission.
If you're buying a donor vehicle, buy one that is 4WD and swap everything.
It's not a difficult build, assuming you've got a stick welder and know how to use it.

Good advise. BTW, doing something stupid is putting a 350 and 700R4 in the that Jeep and using stock Tcase and axles. That engine together with 700R4's deep first gear and torque converter factor could easily over torque destroy your Tcase and axles if you stepped into it hard at wrong time. Right now you have at most about 500 Ft lbs or so of sustained input torque on NP 231 in first gear. With you new combo this can easily hit 1800 ft lbs and more at converter stall going into Tcase and it will takes its toll on your stock parts rest assured. It will be a coin flip to see which blows first, axles or Tcase. Let us know if you go through with it. (I am betting on rear axle in 2wd and Tcase in 4wd.  

ok i agree with some of what has been said and disagree with the rest. i have an 88 yj soa lift and im doing it little by little because of my budget. i threw in a 350 and a sm465 manual tranny. advanced adapters bracket to mate it up with the np231. i put a slip yoke eliminator kit in the back of the 231 and i used tom woods custom drive shafts in front and rear cv of course. i have 35 by 14 swampers on it. and i still have stock axles (30 in front and 35 in the rear). its been this way for two years. beaten the crap out of it at paragon at snow shoe mountain and at the badlands. not to mention countless other places. the 231 and the stock axles have never been a problem. i'm now throwing a high pinion 44 in front and 60 in the rear. 4 linking the front. i do agree that if yer gonna buy a burban just throw all of it under yer yj. but no a 350 wont blow up yer stock 231 or axles.  

You have been lucky and yours is the exception not the rule and quite honestly I am surprised that it has not broken yet. When you build a 4x4 you want to know that odds are that it is not going to break rather than hoping for the best.  

i think if there was going to be a problem it would of happened by now. ive been wheeling the crap out of it for two years. i do agree that there are stronger parts out there that would be more likely to handle up to extreme abuse of rock crawling and foot stomping mud runs. but ive been doing both alot and no problems. i do agree that in a perfect world when you build a 4x4 you want to have the tuff stuff. but if your budget doesnt allow yet dont be afraid to run some smaller stuff. not everyone is going for the ultimate rig or a big budget rig. just get what you can afford for now and go out there and have some damn fun.  

HI THERE IAM DOING THE SAME THING WITH MY 89 YJ IAM USEING A 75 K5 BLAZER WITH A 350 , 350 TRANS, WITH A 205 CASE  WITH A DANA 44 FRONT AND 12 BOLT REAR WHAT WOULD I BE GETTING INTO WITH THIS NEVER DID ANY THING LIKE THIS BEFORE GOT TOOLS WELDER TO DO ALL WORK IS THIS A SMART THING TO DO ???  

IAM FIXIN TO GET IN TO SOMETHING I SHOULDNT OR IS IT A EASY THING TO DO HERE IAM OPEN FOR ADVISE THATS FOR SURE EVEN IF SOMEONE LIVES HERE IN TEXAS TO HELP WITH IT  

I am currently putting an 86 350 goodwrench into my 87 yj. I'm using the transmission (700r) and transfercase (np231) out of a 91 blazer. This combo came out of a blazer with a 4.3L, the 4 banger trans has a different bellhousing and will not work. I've installed a Advance adapter engine saddle and a AA slip yoke eliminator kit. My new rear driveshaft will be approx 18.5 inches from center to center (center of u-joint to center of CV joint). I bought an AA 3 core conversion rad, a B&M trans cooler and am planning on a flex-a-lite black magic electric fan (flx-180). I am not sure if the axles from the blazer would be a benefit to you, but I thought this might save you a couple hundred $$ on the adapter. Also you wouldn't have to rebuild the trans to put in a different output shaft. Be aware that the yj t-case and the blazer t-case have different bolt patterns, so try to get the trans and t-case together and save some headaches.
PS the blkazer tcase has a 1 1/4" chain as opposed to the 1" chain in the yj case. ($340.00 touch from JB conversions).