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Discussion Starter · #1 ·
OK, Here's the scenario:
My brother-in-law rebuilt a Chevy 350 for his Monte Carlo last year. He's now tired of the Monte, and wants rid of it. He was going to pull the motor & junk the body, and I can get the motor.
I have an '85 CJ-7, with an AMC 4 cyl, 150, with I believe, a T-4 tranny.
How much blood sweat & tears (not to mention $$$) will it take to swap motors?

As I figure so far:
New Motor mounts, (no problems with welding)
New radiator ( will I need a new grille because mine is a 4 Cyl?)
New Clutch assembly
New exhaust
Will I need a different oil pan?
I know a conversion Bellhousing will be needed, but are there cheaper alternatives than brand new? And will I be able to retain my hydraulic clutch?
Will I be able to reuse either driveshaft?
The Jeep is a daily driver, with some beach running, & not much else, (nothing BUT sand on Long Island, NY)

The 150 is getting tired, and I was considering a rebuild, but thought this seemed like a lot more fun project.


Discussion Starter · #2 ·
Robert, I don't know much about the engine swap other than the Checy 350 is very desirable.

This weekend the Long Island Off-Road club has a trail run out in Suffern, NY. It's probably an hour and a half ride from Suffolk County. Are you a member of a club right now? Why don't you join us this weekend, the trail isn't very hard. I did the trail back in Nov. 99 with a stock 85 CJ7 258 T176 running 33's with just a body lift at the time.

Let me know if you need more info.

Good luck with the 350 conversion.

[email protected]

Discussion Starter · #3 ·
I think you will need new springs. The 350 should weigh a considerable amount more and you stock springs will sag under the weight.

Cut to shape, hammer to fit, paint to match /wwwthreads_images/icons/wink.gif
Project '51 willy's total rebuild /wwwthreads_images/icons/cool.gif

Discussion Starter · #4 ·
I think that your 350 will bolt right to your bellhouseing.
BUT from all I have been told the t-4 will not hold the power.
How many rows in your radiator . they can have the the hose inlets
can be changed by a radiator shop.Springs I have never seen where
if you buy spring they asked what engine you have except OME.
could use your bell houseing and buy a jeep t-18 ???? I don't know if that would
bolt to your tranfercase.???


1,134 Posts
Go for it, plan to spend some money but it's not all that expensive. The adapter to the bell housing or to the t-case is a mojor cost. I would suggest going with a chevy tranny (TH350 auto, or NV4500 standard) and then adapting it to the t-case ($500ish for adapter). As far as the springs go, put some add-a-leafs up front to keep the sag to a minimum. This is a quick cheap fix that worked for 2 yrs for me until I got new springs. If you place your motor mounts correctly, you can keep both driveshafts. What do you mean by "will I need a different oil pan", I guess you are concerned about the stock 350 sbc oil pan causing clearance problems? this isn't a problem, the stock pan works fine. Go to my home page for more info on my conversion, electrical and mechanical problems I ran into.

/wwwthreads_images/icons/cool.gif Big Ed
'88 YJ, 4" susp,3" body,33's,283 Chevy V8,TH350,4.11's,D30,D35c

Discussion Starter · #6 ·
I'm pretty sure the 350 will not bolt to a T-4. You have an AMC4 cylinder which is different from the GM151 4 cylinder used on 81-83(approx) CJs. The GM151 has the same bolt pattern as the 350. If you insist on using the T-4 you will need a bellhousing that came off a GM 151 4 cylider. I am planning on swapping out my 151 for a ford 5.0 in the near future. If you are still in the market for the bellhousing let me know and I will let it go for very cheap after I do the swap.

83 scrambler


418 Posts
You most likely have the GM 151 motor (my 82 did). As everyone mentioned, the trans will not hold up long (it will behind my 229 V6, until the next rebuild). Here is what I learned from my 229 swap:

The yokes will need to be replaced from the strap on yoke style to the u-bolt style. The strap on ones lasted about three days after I did the motor swap. There is a page that you can find this info on the swap NOTE: The yokes for the Dana 20 transfercase and the Dana 30 front diff are interchangeable and can be used on the Dana 300 transfercase.

Had to get 153 toothed flywheel to fit a GM motor.

I kept the transmission setup and had to get a clutch (pressure plate and throwout bearing) for a 307 Pontiac (10 splinded 10 3/8" wide and had a 1 1/8" input shaft hole). So, if you go with the NV4500 and it has the same spline count, this is a clutch you can get and it will work. Also, your bell housing should fit the NV4500 (I think, I've been told it will fit it as well as the SM420 that is in the works of being installed). So, you get lucky there.

That's about it. Oh yeah, if you keep the fan shroud, you might have to cutoff a chunk of it. I did.....thank heavens for the sawz-all.....

Discussion Starter · #8 ·
Sounds to me like you have a pretty good grasp of the situation regarding this swap. I'll just try to address your questions.

Motor Mounts-I'd recommend MORE's mounts over all others

Radiator- unless you have the towing package with the HD radiator I'd recommend buying a Chevy compatible radiator from Mepco

Your grill will be fine.

Oil pan should work fine unless it is a very, very deep aftermaket design.

It is possible to set this up and keep both original drivelines.

The exhaust is easily handled, many choices available to you.

Clutch, clutch linkage, etc. all depends upon your choice of bellhousing and transmission. This is where it gets tricky. As others have mentioned, the T-4 isn't really up to V-8 power. It is possible that it could last you for quite a while, but I would count on relatively short life. If you want to keep the T-4 Advance has a bellhousing that lets you use the stock hyd. clutch linkage. There many options open for you if you decide to swap trannys. My first question would be: What trans is in the Monte? A TH-350 automatic perhaps? You might want to consider it.

I have done several Chevy swaps into Jeeps. Give me a shout if you need more info. email--- [email protected]

My other car is a BULLDOZER

Discussion Starter · #9 ·
i thought the chevy 350 weighed less than the 258 is that true? also you guys are talking about a 4 banger, did they use a diffrent springs that the 258?

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