Engine Swap 1985 CJ7

[RedRaider43]

Team,
I recently purchased a 1985 CJ7 that is in awesome condition. The Jeep currently has a 2.5L AMC I4 motor and Borg-Warner T-5 Transmission . I am trying to figure out a cost effective combination of V8 and appropriate Transmission for a swap. Any advice would be greatly appreciated.

 

[Peanut Butter]

:ww: neighbor. The question you are asking is very broad. The answers are many and all very different. What you do here should depend on what you plan to do with your Jeep and how you plan to 4 wheel with it. That being said, here is a article you might want to read: https://www.novak-adapt.com/knowledge/engines/swap-guides/chevy-buick-gm/cj5-cj7-80-86-swap/ Do you want to keep the Jeep pure Jeep? Then you need to look at the AMC engine options. With a V8 are you comfortable with the exhaust running outside the frame? That is how most are done, but it can run inside on some V8 swaps. Do you really need the power of a V8? How about gas mileage? Is this a daily driver? Will you take it off road a lot, or just once in a great while. What kind of off-road will you do? Around here the trails are not extreme. Do you plan to go somewhere else with it for 4 wheeling. All of these questions need to be answered before the engine & Transmission experts can answer your original question. Also we would love to see a picture of your new Jeep too!

 

[Lumpy Grits]

:ww:

Do you have any SMOG laws to worry about?
All the swap takes is $$$$$. What's your budget for this.
LG

 

[RedRaider43]

Guys,
I may or may not have a problem......I have multiple Jeeps. I have a 1984 CJ8 Scrambler, 2003 Jeep TJ and the mentioned 1985 CJ7 . The TJ is for if I want to play in the mud, the Scrambler is the queen and the CJ7 is going to be the sleeper hot rod. I want it to look vintage but with modern amenities. This is not a daily driver. I do not rock craw. I envision this Jeep driving back roads of Texas or cruising to the river with my Labrador.

Engine $6K-$7K installed
Transmission $1,200.00 installed

I am considering the following for this build.

Chevy 350/AMC 304 / Ford 302 (Turn Key Engine $6K-$8K installed)
T-176 4 Speed (Currently what I have in the Scrambler and has been very dependable) ($1,200.00 installed)
2.5" Lift w/Fox Shocks ($1,700.00 Installed)
Fox Steering Stabilizer ($200.00 Installed)
Big Daddy Offroad Steering Box Bracket ($200.00 Installed)
BFG K2 ($1K Installed)
American Racing Outlaw II Wheels ($800.00 Installed)
Misc. Interior Fixes

I am trying to figure out what the most cost effective/easiest way to accomplish the engine/Transmission swap is. I do not plan on installing the engine/Transmission myself but I wanted to make it as easy/clean as possible.

 

[Lumpy Grits]

Not wanting to do the install yourownself, will turn this into a money-pit PDQ.
You would be better off ask the folks who will do the work for you what they would use.
ALSO-Get references from these shops BEFORE you commit to any of them.
LG

 

[RedRaider43]

I agree with the money pit issue......

That is why I am reaching out to the wonderful Jeep community to see where the pitfalls are. If I could do anything I wanted it would be to find a AMC 304 and tag it to a T-176 use a couple of adapters, new engine mounts and away we go.

Has anyone else done that type of install?

 

[Lumpy Grits]

Go for a AMC, 401 over the AMC 304
The 2 interchange in mounting........
You want the 4-bolt main that came out of the AMC Ambassador Interceptor police cars.
LG

 

[tarry99]

Red,

"and the CJ7 is going to be the sleeper hot rod."



And asleep or dozing off it would be with that under powered antiqued AMC 304 V8 in it...........

Do this: Chevy LS376 430 HP with the 4L60e 4 speed with Overdrive behind it. Get the connect and cruise package which is all plug & play.......and no problem with driveshaft length as the 4L60e is about 3" shorter than the GMTH400 that is optional that year.

Lots of options to make that into a screamer.......and still yet be very capable off road..........Dana 300 can go 4 to 1 ratio or change your axle ratio's or both.........The 4L60e is 70% in OD so even with low axle ratios combinations , it will still cruise at 75 mph.

Right the check!

 

[Lumpy Grits]

That 4l80e would last much longer.
LG

 

[HackFabrication]

Chevy 350/AMC 304 / Ford 302 (Turn Key Engine $6K-$8K installed)
T-176 4 Speed (Currently what I have in the Scrambler and has been very dependable) ($1,200.00 installed)

I am trying to figure out what the most cost effective/easiest way to accomplish the engine/Transmission swap is. I do not plan on installing the engine/Transmission myself but I wanted to make it as easy/clean as possible.

What sort of engine are you looking for? Used? Rebuilt? Crate motor? How about the Transmission ? Used? Rebuilt? The T-176 uses the Ford 'butterfly' bolt pattern. Simplest way to use that Transmission is either with the AMC engine/bellhousing, or go all Ford. Either way, you are going to have to source parts for the swap.

I don't know what labor rates at shops in your area are, but up here (in Michigan) it's $90 per hour and up for mechanical work. The reality of hot rod shops is not like the shops shown on reality TV. Most places work at a 'time and materials' rate.

Not wanting to do the install yourownself, will turn this into a money-pit PDQ.
You would be better off ask the folks who will do the work for you what they would use.
ALSO-Get references from these shops BEFORE you commit to any of them.
LG

^^^^ What he said.

I agree with the money pit issue......

That is why I am reaching out to the wonderful Jeep community to see where the pitfalls are. If I could do anything I wanted it would be to find a AMC 304 and tag it to a T-176 use a couple of adapters, new engine mounts and away we go.

Has anyone else done that type of install?

Not the AMC route. I went all Ford: 5.0L mated to a Ford T-18 and adapted to the Jeep Dana 20 Transfer Case .



Bear in mind, that one of the weak links in your plan is going to be the axles. The rear AMC20 has 2-piece axles, and thin tubes. Put a bunch of torque to it, without gearing it appropriately, or upgrading the axles, will cause premature destruction. If you really want to build a 'sleeper', then I see a Ford 9" in your build.

 

[Lumpy Grits]

110%, RITE ON.

:ty:

LG

 

[tarry99]

That 4l80e would last much longer.
LG

Last longer? perhaps in the right application.

The 4L80e is first a 113 lbs heavier than the 4L60e but yet both have just about the same rated torque capacity........the 4L80e is also almost 5 inches longer than the 4L60e and 2 inches longer than the OEM GM Turbo 400 which puts the rear driveshaft in a bad way. Notwithstanding that its girth makes exhaust routing in a Jeep a PITA......and with it's 2:48 low gear as compared to the 60e's 3.06 leaves allot on the table...........

I would agree with you if the vehicle was much longer , towed all the time and weighed in much heavier than a 4000 lb. Jeep.

I have a 4L70E behind a 500 hp LS376 that is going in my latest project.

 

[HackFabrication]

If I had the driveline room, there would have been an upgraded AOD behind my Ford 5.0L and mated to a Dana 300 . Ford AOD 87 & Earlier to Jeep Dana 300 Transfer Case Adapter

Alas, the CJ5 doesn't have the room available for a big Transmission , unless you start shoving the rear end back, or pushing the engine forward. Both create challenge$....

 

[tarry99]

GM is releasing there new 4L75e as week speak at SEMA this week..........using the same small compact case as found in the 4L60-70's that will have a whopping 650 ft lbs of torque strength........which will easily get you 4L80e strength in a smaller , lighter & shorter package..........which pretty much makes the bulky 4L80e obsolete unless it's going in a larger frame and body package.

Further good news is I'm hearing that the parts will all fit in the earlier version 4L series transmissions.........although a reprogrammed Transmission controller will be needed.

 

[Lumpy Grits]

That new 'box' would do well behind any diesel engine.
I really do like the 4L80 in my 1ton dually with a 454.
LG

 

[Neuner]

I'll have to keep a look out for your rides. Don't recognize the scrambler. Take it out much?

I commute in a BBQ satin black CJ7 up and down 281 everyday.

 

[RedRaider43]

Hey Guys,
Here is an update on where I am at with the swap.

Dana 300 (OE)
2007 LS 5.3 (Rebuilt)

I am considering using the Novak Adapt setup. Has anyone used it? Pros and cons. Is there a competitor I need to consider?

 

[RedRaider43]

@Neuner

I run the Scrambler/CJ7 /TJ up 281 and Blanco Rd to Smithson Valley as much as possible. I am going to try and go out to the NB Jeep Club Winter get together this Sunday.

 

[Hedgehog]

I really don't know much about your specific application, but it's hard to beat most anything that NOVAK or Advanced Adaptors produce. Neither company is inexpensive.