To restore or to refurbish...

[Drewski]

Hello all...apologies in advance for the long post.

Well, I had trouble sleeping last night; tossed and turned for 2 hours or so before giving up and getting out of bed. Of course the first thing I did was get on here and look at things I could do to my Jeep. Bad idea - haha!

I keep jumping back and forth to doing a full frame-off restore or just slowly refurbish it a few parts at a time. Granted, I've never done either on a vehicle before but my brother in law has already agreed to help as much as possible (he rebuilds classic cars as a hobby) so I've got that going for me.

The frame is in good shape, I'd say an 8/10. Going to get it checked professionally soon. Suspension-wise, going to replace everything. It's all shot.

Next, the AMC 304 , tranny, and Transfer Case have seen some hard times and I've got a mind to swap in a crate 350. I have no idea what Transmission & transfer case to toss in with it however. My only stipulation is that it remains manual.

So, at last, here are my questions and requests for opinions:

1) Are OEM axles/differentials okay with this extra HP & torque? Would it be more economical to get something different?

2) Which trans/transfer case combo would you go with?

As for the body, I'd love to restore it to it's original glory, but that is a bit less important for me than the driveline/drivetrain, chassis, etc. Any suggestions of a good shop to check my frame in the Houston area would be appreciated!

Lastly, this is going to be mostly a weekend warrior, heading to the beach for some 4-wheeling, out to my ranch etc. I really want it to be road-worthy for camping trips as well. I want to eventually pass this down to my son or daughter if I'm blessed enough to have either.

Would it be best to get the mechanics all sorted first, then worry about the body, or just go straight in for everything? Is my budget of $15k realistic?

All opinions and suggestions are welcome. Cheers!

How she looks now added below.

 

[Hedgehog]

Not a bad lookin' rig.

I'm just wondering, why is the suspension shot? Would a simple upgrade in bushings bring her up to where you want to be? The old girl already has a big ol' set of tires, does it run with those? Frankly I wouldn't go any bigger. Or are one of those guys that simply HAS to lift his Jeep?

Axles, it doesn't take much reading here to see that running anything the size of a lawn mower engine seems to require an up grade of your AMC20 axle to a one piece axles. Probably a good idea, but I put a lot 70,000 miles on an '80 CJ5 and never had a lick of trouble with mine. The upgrade does seem like a good idea though.

I believe there's nothing wrong with the drive train you've got. The AMC 304 is a decent engine backed by a Transmission that can handle it. That is unless you are a guy that likes horsepower and showing off a little. Lets face it at 27 we all had some of that in us.

I'm not a big fan of swapping in a Chevy engine. Granted they are VERY cool, but I don't like the way they make power. The AMC is a low end torque engine, they build power differently from the Chevy who is a snappier engine. The snappier engines crack Jeep frames.

If you have holes in the body you need to fix them right away, don't let the rust run wild.

I know one thing, if I had a brother in law that did full restorations I would be itching to prove that I can do it too. A jeep isn't a bad place to start. The body work is relatively simple and what is there to fit, the hood. No doors to worry about, little glass. Also the jeep is fairly light weight. Perfect for a home garage project.

 

[IOPort51]

Is this your DD??

 

[HackFabrication]

Oh boy.... I'm going to keep this as brief as I can. And you're going to have to trust me, as I've dumped WAY too much $$,$$$ into my own CJ5 project.

I keep jumping back and forth to doing a full frame-off restore or just slowly refurbish it a few parts at a time. Granted, I've never done either on a vehicle before but my brother in law has already agreed to help as much as possible (he rebuilds classic cars as a hobby) so I've got that going for me.

Working on this old junk is a complex equation containing many variables. Every one of those variables, has an effect on the other variable's value. And the total cost of the project. Variables equate to $$,$$$. Time is also a function of $$,$$$. Take too much time doing the project, you will again effect the variables of the entire project. Example: Replacing old parts with new parts, then letting them sit for five years, requiring you to replace the new parts with... new parts.

Nice you've got someone to 'assist'. Just hope he's around for the duration of the project.

The frame is in good shape, I'd say an 8/10. Going to get it checked professionally soon. Suspension-wise, going to replace everything. It's all shot.

Having a good frame is paramount to any resto. Jeep CJ frames are notorious for rust and tweaks. If you're going to do a total 'frame off', have it checked after it's been stripped.

It appears there is already a lift on the CJ. Appears to be in the 2.5"-3". If you haven't spent a lot of time in short wheelbase, narrow track, straight axle, leaf sprung vehicles (especially with the forward placed front shackles like on the CJ's), with big bias ply tires and stiff sidewalls: These are going to ride ROUGH. They rode rough off the showroom floor. Not much you are going to be able to do, other than make certain all the bushings, ball joints, tie rod ends, and shocks are in tip-top condition. Doing this will give you a degree of predictability, as to where the vehicle will be tracking. Otherwise, it may just randomly pick where to track.

Next, the 304, tranny, and transfer case have seen some hard times and I've got a mind to swap in a crate 350. I have no idea what transmission & transfer case to toss in with it however. My only stipulation is that it remains manual.

Well last first: It's a CJ5, automatics are a tough fit in a CJ5. Jeep NEVER offered a CJ5 with an automatic due to the short rear drive shaft that would result. But owners have installed autos. Most common would be a TH350 behind a SBC.

You show a AMC 304 /T-5 /Dana 300 combo in your 1980 CJ5, but Jeep didn't offer the T5 (5spd-OD) until 1982 (Jeep Transmissions: T-5). The 304 V8 was available until the 80-81 model years and was in quite a few CJ5's (Jeep Engine: AMC 304 V8). I believe the OEM offering in a 1980 CJ5 with the 304 V8 was the T-176 . The SR4 or T176 was available with the 4 cyl 'Iron Duke' GM 151 or the 6 cyl AMC 258 i6 / 4.2l (4.2L). The Dana 300 made it's debut in 1980 replacing the Dana 20 , and was used in all CJ models until the last production in 1986.

If you have a T5, it was swapped in by a previous owner. I'm not going to get into all 'good, bad, and ugly' of the T5, but I will add that there are quite a few CJ owners running them with little or no issues. You just have to know what they can and can't do. There is a local Jeeper that has a CJ5 with a warmed over 258 (MoPar 4.0 head and EFI, etc.), running 35's (properly geared) and a T5. He has been over all the major trails (Rubicon, Moab, etc.) with it. So they aren't the box of that a lot of people say they are. Big horsepower/torque is a definite T5 killer. Big tires with poor gearing will also hasten it's demise.

1) Are OEM axles/differentials okay with this extra HP & torque? Would it be more economical to get something different?

Depends on how much horsepower/torque you are going to be sending them. Remember: Gearing multiplies torque. The stock AMC20 rear has a few known weak spots. First being the 2pc axle shafts. Second the thin axle tubes that also tend to spin in the diff housing. You can upgrade to 1pc shafts (I'd recommend Moser), truss the axle, and weld the tubes. All depending on what size tires you intend to run. On my CJ5, I did everything but truss the axle. The other weak area is the flimsy 'Dough Boy' differential cover. Prone to bending, but can be replaced with a sturdier cast aluminum, or heavy steel piece. In 1980 Jeep CJ's had 10"x1.75" rear drums (earlier CJ's had 11"x2" drums). Adequate, but can be stressed the larger the tire that needs to be stopped. If you're going to run tires above 30", IMHO, you should be also looking into power brakes (if your CJ5 doesn't have them).

The Dana 30 front axle is good for up to 35" tires, depending on a lot of variables. Mostly driver input. Spinning large tires, lockers, drive line 'shock' from suddenly gaining traction, will grenade the u-joints and/or lock out hubs. IIRC, your 1980 should have the Premium 6 bolt Warn locking hubs, which are sturdier than the 5 bolt version found in the later CJ's.

2) Which trans/transfer case combo would you go with?

For what you describe as intended use, I would either keep the T5 (and live with it's limitations), or look for a T176 (4spd). An AX-15 (5spd-OD) or NV35xx (5spd-OD) is an option, but modification/adapting would be necessary. In most instances, the terms 'modification' and 'adapting' mean $,$$$.

The Dana 300 Transfer Case is an excellent unit. Keep it. There is a ton of aftermarket support for that unit. The aftermarket cases (Atlas and STaK) are patterned after the Dana 300, so it's a proven design. In a CJ5, you need to keep the entire drive train as short as possible, otherwise you end up with a very short rear drive shaft with a very steep angle. You can mitigate some of this with a CV type rear drive shaft, but there is only so much you can do about the length (other than move the engine forward or rear axle back).

As for the body, I'd love to restore it to it's original glory, but that is a bit less important for me than the driveline/drivetrain, chassis, etc. Any suggestions of a good shop to check my frame in the Houston area would be appreciated!

See my comments on body work.

Honestly, I would just do a light 'resto-mod' on it. Keep the 304 (rebuild it), the T5 (rebuild if necessary) and adjust tire size depending on your present axle ratio. Second would be to snag a T176 and install it behind the 304. If the 304 proves too gutless for you, then drop in an AMC 360.

Can't help ya about the Houston area (other than my daughter and future SIL live in Cypress)...

Lastly, this is going to be mostly a weekend warrior, heading to the beach for some 4-wheeling, out to my ranch etc. I really want it to be road-worthy for camping trips as well. I want to eventually pass this down to my son or daughter if I'm blessed enough to have either.

All I can say is KISS.

Would it be best to get the mechanics all sorted first, then worry about the body, or just go straight in for everything?

Really depends on how in depth (I should say in debt) you want to go with the resto. Removing the body from the frame is a relatively easy process. At that point you can separate the various mechanical 'parts' and work on them. CJ's are simple vehicles. Unless you make them otherwise.

Body work, if you have the skill, tools, time, and space is fairly straight forward. Of course, you will need a decent air compressor to paint. Air tools (sanders/grinders) are almost a necessity, along with a welder. If you want a showroom quality paint job, the prep work is paramount. Lots of: sanding/sealing/filling/sanding/filling/priming/sanding/filling/priming/sanding, before the final color gets sprayed. If you have to pay someone for this, the sky's the limit, all depending on the final product.

Is my budget of $15k realistic?

Again depends on what your expectations are for the finished vehicle. You want it to look as good as a new vehicle and to be as dependable as a new vehicle? I don't $15k will do.

Now the stuff you're not going to like...

If you are convinced you want the CJ5. Fix what's broke that is necessary for safe operation. Drive it for a couple of years 'as is'. Then decide how much time/effort/money you want to dump into it. You might just find the next option the best (and it's one that I wished someone had talked me into back in the late 90's).

Take the $15k, and find yourself a nice used Jeep TJ Rubicon Unlimited. You will still have ample opportunity to get your hands dirty. You will be a heck of a lot more comfortable driving it. It is as capable stock as any CJ ever was. And it's also got a nice amount of aftermarket support for upgrades. The aftermarket for CJ 'stuff' is dwindling, IMHO. Most of the 'neat stuff' needs to be hand fabricated.

These old CJ's are heartless that will push you down in the muddy playground and steal your lunch money. Then laugh as they walk away.

You've been warned. Good luck, (because I know you're not going to listen to me). :grinjeep:

 

[IOPort51]

Good post Hack!!

CJs are not for everybody, you have to become proficient at a lot of new skills and even enjoy them.

Unless, of course, you are independently wealthy and can pay someone else to do it for you. But I must add that the "buy everything" experience will not serve you well when broke down 3 miles from the geographic middle of no place. Then you kind of need to know how everything works.

It is great therapy for my ADD!

 

[somedude922]

Another option might to buy a cj that already has a lot of the big work done. That's what I did. The drivetrain was already finished. I just add my own touches to the jeep and perform weekend maintenance on it. I'm willing to pull things apart to reseal and learn as I go. Eventually I will really dive into the jeep when my boys are older and do a restomod on it. For now we are just enjoying it and fixing as it breaks. As a weekend wrench on it for the next several years I learn that much more in preparation for the big project in the future.

Good luck!!

 

[Hedgehog]

Hack - Great post, your honesty and integrity has gone up (even more) in my book. Well thought out posts aren't as easy to actually write well as many would think.

 

[HackFabrication]

Hack - Great post, your honesty and integrity has gone up (even more) in my book.

Thanks!

 

[Drewski]

First, a big thanks to all of your advice and opinions, especially Hack! I really appreciate how in depth you got with my questions and even answered things I didn't know to ask. Your personal experience with your own CJ5 project seems very extensive!

Secondly, I also appreciate the warnings as to how expensive restoring one of these bad boys can be. I did, however, know that when I bought it. Originally I just wanted to get it ready to pass an inspection and call it quits. Now just driving around in it for a couple weeks has got my pride swelling and I can't leave it as it is. Also, I do understand I can get a newer, more comfortable, and more reliable Jeep for my $15k...but that's not an option. I've got a 4x4 truck for that. Again though, thank you for the advice.

So...since I've decided to stick with it and after thinking on it longer, I'm going to go with Hack's advice to just do a light "resto-mod" for now.

There is indeed about a 3" body lift and 33" tires on it...which I hate. I'm a shorter guy so having to jump and contort to get in isn't going to work for me.
After fixing the steering box bracket, I've ordered new tie rods, drag link, pitman arm (original was twisted), leaf spring bushings, and ball joints. How can I tell if the shocks need to be replaced? I have no idea what these Jeeps are supposed to feel like but I do know it rides really rough right now. Sounds like I'll just have to get used to it I suppose.

I do know from the PO that the engine and Transmission were replaced "Oh around 25,000 miles ago by the PO I think." So 2 owners ago...that was done. I have no idea when or the actual miles on them. There are some nice leaks coming from both though. Only reason I suggested the 350 swap is because I know more about it and have the cash laying around. Sounds like it would require more work however. I really do like the idea of keeping the AMC 304 in it but have no idea what "rebuilding" it entails.

Considering I keep what is in it the drivetrain, what size tires are decent for this rear axle? I was of the mind of 31" but not sure if I need to leave a lift on it or not. I'd rather not. Also, I had previously decided to convert it to a power brake system. I appreciate being able to stop with much less effort!

The body has very little rust, thank the lord. Again, repairing/refurbishing it will be the last thing I do, but definitely something that's going to happen.

Again, thanks for the info...I still have loads and sure I will come up with even more questions as I move along with fixing this bad boy up! This forum rocks!

 

[HackFabrication]

First, a big thanks to all of your advice and opinions, especially Hack! I really appreciate how in depth you got with my questions and even answered things I didn't know to ask. Your personal experience with your own CJ5 project seems very extensive!

You're welcome. And the operative words should have been: very expensive.

Secondly, I also appreciate the warnings as to how expensive restoring one of these bad boys can be. I did, however, know that when I bought it.

Like I posted earlier, cost is a factor of time/labor/parts. You can hold costs down by doing a lot of the 'simple' things yourself. Depending on how 'deep' you go into the project, you will most likely need to farm some of the work out. I don't know what the cost of automotive related labor is in your part of the country, but it is approaching $100 an hour up here, if you need to go to a shop.

The shop where my CJ is at, charges $90 an hour for anything mechanical. Body shop rates are $65. When paying someone else to do the work, you have to be vigilant, or the bill will get completely out of hand.

So...since I've decided to stick with it and after thinking on it longer, I'm going to go with Hack's advice to just do a light "resto-mod" for now.

On the plus side, it appears you are starting with a decent vehicle, not the $500 POS that followed me home in 1996:



IF... IF... You decide to tear it down, remember:

1) DO NOT THROW ANYTHING AWAY! The aftermarket has a lot of replacement parts. They don't have ALL the replacement parts.

2) Take plenty of digital pictures: Before, During, and After removing any part.
Place bolts, nuts, screws, clamps, hoses, etc. back into the part you removed them from. The automakers have a habit of using bolts that are either 'a bit longer' or 'a bit shorter' than what you can get at most hardware stores. They also used different grade bolts in different locations. You'll want to replace them in the exact spots.

3) Place small parts into plastic (ZipLock or other) bags. Label with a permanent marker. Put the small bags into a large and labeled plastic storage tub. Put the tub somewhere that it won't get thrown out.

4) People helping are fine, just do not let them get ahead of you. They may not be around when it comes time to put everything back together. See 1, 2, & 3.

5) Don't 'force' anything. There will be a number of bolts, fasteners (Torx), that will need finesse (heat, grinding, other tricks) to successfully remove. The last thing you want to do is ruin a good part by removing a bad part. But it happens.

6) AGAIN: DO NOT THROW ANYTHING AWAY! Keep even the broken stuff until you've got a replacement in your hands and that will fit.

7) When you get upset, mad, po'd... Walk away from it. Working on it when you're in the wrong mood, will create extra work for you. And extra expense. Better to 'let it sit', until you both have a better attitude.

There is indeed about a 3" body lift and 33" tires on it...which I hate. I'm a shorter guy so having to jump and contort to get in isn't going to work for me.

Doesn't look like a 3" lift, but post up a pic of the body mounts. 3" of BL is a bit much, although it is the cheapest way to get bigger tires under the vehicle. Excessive BL's put strain on the existing mounting points. When you remove it, you will see how the factory attached the body to the frame. On the plus side (hopefully), the bolts, having been removed/replaced should be easy to remove. And, hopefully, none of the caged nuts are spun. Although you CJ appears to have the OEM shackles, it still looks like there is a bit more arch in the springs than stock. Take some pics of them and post, the forum members should be able to provide a 'best guess' as to what they might be.

IMHO, based upon what your intended use is (and that is always subject to change), I would remove the BL, use either rubber or urethane body mount bushings (rubber has a bit softer ride quality). Check the axle ratios both front AND rear - no telling what a previous owner(s) might have swapped in. Nothing worse than having a 2.73 rear and a 3.54 front. If you've got 3.54's AND you want to retain the T-5 (you're certain it's a 5spd? Not a T-176 4spd?), then I wouldn't run anything larger than a 31" tire. That is 70 mph at 2350 rpms in 5th (OD) gear. Trust me, 70 mph in a CJ5 will feel a heck of a lot faster than 70 mph in you 4x4 pickup.

A CJ with stock suspension and '0' BL, can run 30"-31" tires (depending on actual mounted diameter) 'on the street', or very mild trails, without causing problems with the body sheet metal. With the CJ5's narrow track axles, increasing the tire diameter will necessitate adjusting the turning stops on the front axle. Otherwise, the tires will hit the springs and/or sway bar:

After fixing the steering box bracket, I've ordered new tie rods, drag link, pitman arm (original was twisted), leaf spring bushings, and ball joints. How can I tell if the shocks need to be replaced?

The twisted pitman arm is disturbing. Was it a dropped pitman arm? Or original straight? The (straight) OEM is a steel forging. Takes quite a bit to bend it. Most likely, if enough force was applied to the pitman arm to bend it, and the steering box mount to break it, there is potential damage to the steering box.

Did you order ball joints or tie rod ends? In order to replace ball joints, you will need to remove the knuckles. Might not be something you want to do at this point, unless they are trashed.

I have no idea what these Jeeps are supposed to feel like...

Like a Go-Kart on a cobblestone street. Maybe not that bad. There are ways to smooth the ride. Adjusting tire pressure is one. Upgrading to a better seat is another.

I do know from the PO that the engine and trans were replaced "Oh around 25,000 miles ago by the PO I think." So 2 owners ago...that was done. I have no idea when or the actual miles on them..... I really do like the idea of keeping the 304 in it but have no idea what "rebuilding" it entails.

The dreaded PO... Assume NOTHING. Re-read my replies... Even though mine was a POS, it was all original. Until I got a hold of it:





Go buy/rent a pressure washer, get some de-greaser, and blast the oil/grease/ off everything. I wouldn't do it a coin-op car wash. It might not want to start for a bit...

Considering I keep what is in it the drivetrain, what size tires are decent for this rear axle? I was of the mind of 31" but not sure if I need to leave a lift on it or not. I'd rather not. Also, I had previously decided to convert it to a power brake system. I appreciate being able to stop with much less effort!

You really need to determine what the axle ratio is. Check both (see previous). A 'Common' gear ratio from 1980-1986 was 2.73 (an attempt to raise MPG to meed CAFE standards). Other ratios were available.

As previous, IF you have the 3.54 you can probably run a 30"-31" tire and still use 5th (OD). As long as the AMC 304 is still healthy. A 3.73 gearing (with 30"-31" tires) would be better, IMHO, for overall trail/beach/street/highway performance. In 1980 an AMC 304 V8 made a whopping 125 horsepower @ 3200 rpm. And 220 ft/lb of torque @ 2400 rpms. Earlier 304's did a bit better, but HP/TQ ratings are always suspect. Based upon where the max torque is, in 5th (OD) gear, running a 31" tire, the engine would be turning 2350 rpms at 71 mph (theoretically). 3.73 gearing would see 2260 rpm @ 65 mph. Plenty fast for a narrow track CJ5. 2434 rpms @ 70 mph. Which still puts the 304 'around' peak torque with the stock internals.

By comparison, my 4.56 geared, T-18 (4spd), 32" tires, is SCREAMING at 3112 rpm @ 65 mph. 3352 rpm @ 70 mph. I don't plan on extensive freeway/interstate driving in my CJ5....

Power brakes are a nice upgrade, especially with larger than OEM tires. Lot's of ways to do it. I'm running a hydroboost system from VANCO:





There are other 'kits' available, and just a whole spectrum of junkyard methods.

The body has very little rust, thank the lord. Again, repairing/refurbishing it will be the last thing I do, but definitely something that's going to happen.

Until that time, do your best to keep the surface rust in check.

Good Luck.

 

[Drewski]

Hack, again you outdid yourself with information. Thanks!

I'm out of town for work but will post up pictures of the body mounts and springs here when I return.

To answer your question, I ordered both ball joints and tie rod ends at the advice of my mechanic. The steering box bracket was not actually broken, just very loose; a few bolts were missing. The bracket itself looks brand new. The pitman arm was not a dropped version. It is straight and looks like the original. The twist wasn't severe, but definitely noticable. I read somewhere it is desirable to have the original steering box rebuilt instead of opting for a new one?

In regards to my Transmission , it is definitely a 5 speed and the only thing I could make out on it was the Borg Warner brand. I haven't cleaned it all up yet to look for other numbers. After doing a little research last night, it seems like this T-5 is basically a car transmission. Makes me wonder why the guy put it behind this AMC 304 ? I'm not overly partial to 5 speeds but the Overdrive option is nice. I was on the Novak website and saw that an AX15 is a good option for what I have now if I wanted to keep a 5 speed, or the T-18 , or as you mentioned, a T-176 . Are there any pros to having a 4 speed over a 5 speed?

As far as the axle ratio goes, I have no idea what it is. This is where my knowledge ends when it comes to vehicles; axle ratios have always confused me. You seemed to be doing some pretty fancy math, which I'm not scared of, but where were you getting the formula to calculate the RPM @ a certain MPH with a certain gear ratio? Also, why did you suggest a 3.73 would be a good "all around" gear for what I have in mind....forgive my ignorance. Is replacing the gears in my differential fairly straightforward?

I do see the benefit of putting a single shaft into my AMC20 however, so that will definitely happen. When you say "weld the tubes" I'm not really sure what you mean...rather not sure where to weld them. Thanks again!

 

[HackFabrication]

To answer your question, I ordered both ball joints and tie rod ends at the advice of my mechanic. The steering box bracket was not actually broken, just very loose; a few bolts were missing. The bracket itself looks brand new. The pitman arm was not a dropped version. It is straight and looks like the original. The twist wasn't severe, but definitely noticable. I read somewhere it is desirable to have the original steering box rebuilt instead of opting for a new one?

It's a somewhat big job replacing the ball joints on the front axle. Lot's of 'stuff' needs to be removed. I would hold off until you've determined that they are bad and/or you plan on 'going though' the front axle. Good time would be if you want to change gearing.

There are a number of options for the steering box. Rebuilding the OEM is one. Swapping in one out of, IIRC, a J series truck is another. It's a Saginaw box, which is used in all GM vehicles and some others. Lot's of Junk Yard options if you want something with a better ratio.

In regards to my transmission, it is definitely a 5 speed and the only thing I could make out on it was the Borg Warner brand. I haven't cleaned it all up yet to look for other numbers. After doing a little research last night, it seems like this T5 is basically a car transmission. Makes me wonder why the guy put it behind this 304? I'm not overly partial to 5 speeds but the overdrive option is nice. I was on the Novak website and saw that an AX15 is a good option for what I have now if I wanted to keep a 5 speed, or the T18, or as you mentioned, a T176. Are there any pros to having a 4 speed over a 5 speed?

The T-5 that Jeep used isn't the later 'World Class' version of the T5. It has limitations as to the amount of torque you can run through it. Internally, you will tear it apart with big tires and wrong gearing. There are a lot of CJ's running around with T5's (it was OEM from AMC-Jeep), within it's limits, it's usable and good for your intended usage. The AX15 will handle medium horsepower, it's good Transmission , but will need to be adapted, which means $$$. The T-18 is a heavy duty 4spd. And it shifts like one. With the low 1st gear (un-synchronized) it is basically a 3sp on the street. Unless you find one from a CJ, it will need to be adapted ($$$). The T-176 is a good option, was OEM on CJ's and is a more street friendly transmission in the 4spd group.

As far as the axle ratio goes, I have no idea what it is. This is where my knowledge ends when it comes to vehicles; axle ratios have always confused me. You seemed to be doing some pretty fancy math, which I'm not scared of, but where were you getting the formula to calculate the RPM @ a certain MPH with a certain gear ratio? Also, why did you suggest a 3.73 would be a good "all around" gear for what I have in mind....forgive my ignorance. Is replacing the gears in my differential fairly straightforward?

Bookmark this: Gear Ratio Calculator Best calculator I have found for working out what ratio you would like to run.

Your CJ, most likely doesn't have 3.73 gearing, but it's possible. Having too low (high numeric) gearing will cause the engine to rev too high . Too high (low numeric) gearing lug and/or cause the engine to operate out of it's optimal power band. Installing larger diameter tires will have a similar effect as they will lower the overall gearing and cause the engine to lug.

In a simplified way: When you 'build' an engine, or have a specific engine installed, you should have a specific power band in mind. Looking at the stock AMC 304 torque rating, it starts to drop past 2400 rpm. You should be gearing for highway speeds just below that. But there are many variables.

You can do a simple gear ratio check (assuming there are no lockers installed) by lifting a tire, putting the trans in neutral, mark the tire and spin the drive shaft until the tire makes one revolution. Count the number of drive shaft revolutions and you have the gearing. Same for the front, but make sure you have the hubs locked first. The front/rear only has so many ratios available, and they can be found with a simple internet search. Here's a good site to bookmark: The New Jeep Tech Pages! Go to the Dana 30 and AMC20 pages and see what the available ratio were.

I do see the benefit of putting a single shaft into my AMC 20 however, so that will definitely happen. When you say "weld the tubes" I'm not really sure what you mean...rather not sure where to weld them. Thanks again!

A bead of weld is run around the differential house where the axle tube is pressed in.

 

[87MJTim]

Sorry to hijack this, I love that color of green. What it the shade and color code?

Tim

 

[HackFabrication]

Sorry to hijack this, I love that color of green. What it the shade and color code?

Stock (later model) Jeep color: Natural Green Pearl. Don't have the color code handy.



The color really 'pops' in the sun light.

 

[Drewski]

That really is a nice green. Something to keep in mind for when I eventually paint as well.

Mini-update: I'm still away for work in West Africa...hoping not to catch this f***ing Ebola!

Can't wait to get back to work on my Jeep.

 

[duffer]

I'm not a big fan of swapping in a Chevy engine. Granted they are VERY cool, but I don't like the way they make power. The AMC is a low end torque engine, they build power differently from the Chevy who is a snappier engine. The snappier engines crack Jeep frames.

Chevy's, like AMC's, Fords, or just about any other "modern" V8's will respond pretty much the same way to any given engine configuration. If you put a big cam in a AMC 304 , you will no longer have a torque engine, at least not in any rpm band that is really usable in a Jeep. That absolutely applies to a sbc also, but if you build the sbc for torque, it will be second to none.

That said, I'm not sure a crate engine will actually give one what is needed in a Jeep. At best, I would expect to have to change the cam and possibly the heads at which point it may be better to start from scratch. A 383 version is also something that should be considered. That extra 1/4" of stroke can make a torque monster with the right cam.

 

[cj5 freak]

Does anyone know where I can find stock 78-83 CJ5 soft doors that are one piece with top and bottom door windows with the simple turning lever handle