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I'm a CJ Newbie and Need Major Advice

I'm a CJ Newbie and Need Major Advice

jtbyler

Jeeper
Posts
22
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Location
Tucson, AZ
Vehicle(s)
1977 CJ-7. Stock 258 straight 6 and stock automatic quadratrac (???) transmission.
I just inherited a beat to heck 1977 CJ7 that I would like to completely rebuild. I don't know much about it other than it has the AMC 258 i6 / 4.2l straight line 6, automatic QuadraTrac (???) Transmission and approx. 124,000 miles. I have talked to several people and received advice from "rebuild the current AMC 258 i6 / 4.2l " to "dump the AMC 258 i6 / 4.2l and install a Chevy 327" I will say I don't particularly care for the AMC 258 i6 / 4.2l . Has very little power and not very responsive. I also don't care for the QuadraTrac Transmission . I'm not opposed to a 327, but am unsure of how this engine will affect the rest of the rebuild (transmssion, etc.). As you can probably tell, I am a complete amateur in this field. I understand a rebuild like this will cost $$, but this was my deceased father's jeep so I'm pretty committed to it. Any advice would be greatly appreciated.
 
First off, we talking mid to late 60s 327 carb motor, or a 99up GM light truck 5.3L LSx that many call a 327 ? (but I think is a actually a 325 ?)
 
I say keep it Jeep. If you don't like the AMC 258 i6 / 4.2l put a 4.0 in it then you get FI that is my plan for mine.
 
I'm new to this, so I'm open to anything. I'm not stuck on a Chevy 327, that was something suggested to me. Looking for something with a little more power than the current AMC 258 i6 / 4.2l and something I can somewhat customize (performance wise). Other than that, I am open to pretty much anything.
 
Sorry for being so uneducated in this area. I take it the 4.0 is an AMC engine??
 
Yes, the 4.0L is the newer fuel injected version of the AMC 258 i6 / 4.2l (jeep/Chrysler).

This whole subject, is based on how much you can spend. You can wake up the AMC 258 i6 / 4.2l with a Ford 2 barrle carb, a HEI distributor, and even a header, if you dont want to do the swap.

Do you like have a three speed auto, or do you want a stick, what are you wants, want to go faster ?

A true 327 chevy is really hard to come by, its a short stroke small block, and probably for the dollar a bad match for any jeep or truck, unless you plan to drag race it. Its a high rpm motor, that really belongs what it came in, not jeeps.

Unless someone was making reference to an old mid 60s 327 AMC motor, also not a good choice if you going to do a swap, not sure where you would find one anyway.

If youre doing a chevy, its usually a 350, or a new LSx family motor, if you want the latest.

Do you have emissions testing in your area ?
 
Sorry for being so uneducated in this area. I take it the 4.0 is an AMC engine??

Yeah it is, i Have the 77-7 love it, when you build ur jeep make it what you want and can afford if the motor runs use it the Transfer Case and Transmission work use it! try to keep it running while you do the upgrades, this helps keep the fire alive when building, think it through use forums like this to help you learn what kinda project a jeep can be. do you want a trailer queen or a dirty little mudder? good luck.
 
First, welcome to the wonderful world of CJs. When it comes to motor swaps, to some extent you just bumped the bee hive as there are some very strong opinions here, one of which is mine. Keep your Jeep, Jeep. I freely concede all the accolades of the SBC, it’s a motor that can’t be beat in a hot rod but has little value in a CJ. (My Opinion) There are so few CJs left it’s a crime to butcher the remaining ones up.

You have several options to keep your Jeep, Jeep. One is to just rebuild the AMC 258 i6 / 4.2l and upgrade the carb and ignition system. The AMC I-6 is torque monsters when it comes to low end grunt and it is possible to put a 4.0 head on your AMC 258 i6 / 4.2l for better breathing or just go for the 4.0 out of a Wrangler. If a V8 is what you truly want drop in an AMC V8, a AMC 304 , 360, or 401. (Same block size for all motors) As they were a factory option the swap is as bolt in as you get except for the need to relocate the passenger side motor mount.

As far as dumping the Qudratrac things get a little more complicated as the Quadratec rear end will be offset to the passenger side and the typical Transfer Case swap is going to be a Dana 20 or 300 which require a centered differential. The Spicer 18 Transfer Case is properly off set but none of these transfer cases will bolt up to the Qudratec auto Transmission without reworking the tranny and spending a bunch of bucks.

Speaking of axles the front axle is set up for full time rotation and once the Qudratrac is dumped front hubs are in order (or an axle swap) and that’s a bunch more money.

My point isn’t to discourage you but to show that things may not be as simplistic as they are perceived to be. However planning, finding the parts, and the build are half the fun; just make sure to acquire all the parts needed before you begin.
 
The first thing you should figure out is what direction you want to take your jeep i.e. off road only, 50% off road 50% street, street only, full factory restoration, lifted street cruiser. The good thing about jeeps and the jeep community is that you can find anything under the sun you want to know about it and that ranges from mild to wild.

Once you figure out your direction make a list of the things you want to do. Then group the similar items together. For example if you were going to upgrade to stronger axle shafts you might want to also regear your axles at the same time. This saves you the time of redoing something again and if a shop was doing it, it save you money too.

Do your research. The internet is awesome. You can find threads of other peoples work and mods as well as new parts and the reason someone set their jeep up the way they did.

Its fun and frustrating. Driving a jeep around on a nice day with nowhere to go and no top or doors is one of the best things in the world. Plus people love staring at a good looking CJ. Its also the most frustrating thing in the world when it's parked in driveway unable to move under its own power and a great day is slipping by.

Don't jump in to far over your head but don't be afraid to get in there and do it. You will learn a lot the more you mess with it but don't get frustrated when it doesn't work. Just come back to the threads and someone will remind you about something you completely looked over.

I think that's about it.
 
I just inherited a beat to heck 1977 CJ7 that I would like to completely rebuild....

...... I understand a rebuild like this will cost $$, but this was my deceased father's jeep so I'm pretty committed to it. Any advice would be greatly appreciated.

You thinking restoration rebuild, or resto-mod rebuild?
 
The first thing you should figure out is what direction you want to take your jeep i.e. off road only, 50% off road 50% street, street only, full factory restoration, lifted street cruiser. The good thing about jeeps and the jeep community is that you can find anything under the sun you want to know about it and that ranges from mild to wild.


Its fun and frustrating. Driving a jeep around on a nice day with nowhere to go and no top or doors is one of the best things in the world. Plus people love staring at a good looking CJ. Its also the most frustrating thing in the world when it's parked in driveway unable to move under its own power and a great day is slipping by.

Ah, beat me to it. He really nailed it. I think before you start guessing on an engine and Transmission that you need to define the general question he asked. Keep it stock, go wild or something inbetween? Then let us know about your wish list and give us as much details as you can about it such as what axle ratio you have, etc so that you can receive better direction/heated opinions. There's a lot more than the basic question of keep original engine or go bigger depending on what you want out of it.
 
something to keep in mind if you stick with the QuadraTrac (not my cup of tea) is that the v8's produce power shaped more like a hill where the i6 makes torque flat off the bottom and falls of rapidly after a slight swell in power. with the auto Transmission you have a torque converter in the way that slightly negates the benifit of the off-the-bottom torque of an i6, not that im arguing for a v8, just making a point that can easily be overlooked. personally i would swap to a full manual drive train and keep the i6, but thats just my style of driving. T-18 wide ratio and Dana 20 give you a very tactile and direct connection to the drive train, theres a reason alot of ppl call automatics "slush boxes" you feel much less of whats going on.
 
Guess you might need to take a good look at what your going to do with the Jeep as several have mentioned in this thread. Then take your direction. I have a couple of opinions here like everyone else. First, I recommend you keep it AMC Jeep. If you don't like the I-6, maybe drop in a AMC 304 or 360 ( V-8s ). Secondly, if you have the QuadraTrac , then you will also have the GM TH 400 with is a pretty beefy Transmission for a small vehicle ( If I remember correctly, 76-79 is the only years for the Qtrac and the only AT option was the TH 400 ). Around my area, one doesn't see many 76-79 CJ7 's with an automatic and that makes them kind of cool/unique. Anyway, just my two cents, make it yours and do what makes you happy....its your CJ7 . Keep us posted.
 
So is your head spinning yet :D
 
Yes, we have emmissions testing. I'm not opposed to sticking with the AMC 258 i6 / 4.2l if I can put a little more pep into it.
 
Ha ha. Yes, definitely. I've made up my mind and changed it about a thousand times. But enjoying every minute of it.
 
Guess you might need to take a good look at what your going to do with the Jeep as several have mentioned in this thread. Then take your direction. I have a couple of opinions here like everyone else. First, I recommend you keep it AMC Jeep. If you don't like the I-6, maybe drop in a AMC 304 or 360 ( V-8s ). Secondly, if you have the QuadraTrac , then you will also have the GM TH 400 with is a pretty beefy Transmission for a small vehicle ( If I remember correctly, 76-79 is the only years for the Qtrac and the only AT option was the TH 400 ). Around my area, one doesn't see many 76-79 CJ7 's with an automatic and that makes them kind of cool/unique. Anyway, just my two cents, make it yours and do what makes you happy....its your CJ7 . Keep us posted.

Thanks for the advice. I like the idea of keeping it an AMC jeep. A good friend who rebuilds classic cars gave me the same advice. He gave me a couple of ideas for adding a little pep to the AMC 258 i6 / 4.2l . He also suggested I stick with the QuadraTrac . I've pretty much decided that's the direction I want to go. I can't wait to start the engine rebuild. Will definitely post some pics and keep you updated.
 
Yeah it is, i Have the 77-7 love it, when you build ur jeep make it what you want and can afford if the motor runs use it the Transfer Case and Transmission work use it! try to keep it running while you do the upgrades, this helps keep the fire alive when building, think it through use forums like this to help you learn what kinda project a jeep can be. do you want a trailer queen or a dirty little mudder? good luck.

I've received the same advice from a lot of people I've talked to locally. Definitley makes sense. Don't want a trailer queen. I'd like to end up with something I can take off-road, but my wife has already told me she can't wait to drive it around town :) So, I'm hoping to end up with something in-bewteen. I definitely appreciate all the the help.
 
I also agree with the other comments concerning keeping it AMC factory. The only thing I would recommend is switching out the 3 speed automatic for a 4 speed manual. That would definitely give the AMC 258 i6 / 4.2l a little more pick up.
 

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