CJ rear AMC 20 disc brakes

coxhaus · 03-23-2008, 02:23 PM

I am wondering how many of you have installed disc brakes on your AMC20. Do they work a lot better and did you connect the parking brake up? Does your CJ stop better? Which parts did you use for the disc brakes? I have a 79 CJ 7 with ten inch rear brakes with 33" tires. The Jeep does not stop very well and I have to rebuild the rear brakes all the time. I need a solution with a parking brake due to Texas yearly inspections.

Mr.Crowley · 03-23-2008, 05:22 PM

i pulled the 20 outa my project jeep and it had the kit from TSM..It did stop very well with 35's and manual brakes..They use an eldorado brake caliper with an intergrated parking brake lever..From the looks it reuses the stock e brake cables..I am pulling them off to put on my mud jeep,cuz I have fried too many shoes..About 2 sets a summer..

Mudslide · 03-23-2008, 08:22 PM

There was a guy on Ebay selling the brackets to use 300Z calipers and Suzuki Sammy rotors. I don't rember the details though.

GPER · 03-24-2008, 05:32 AM

This maybe some help
http://www.pirate4x4.com/forum/showt...=nissan+suzuki

Stan99 · 03-24-2008, 11:52 AM

Quote:

Originally Posted by Mr.Crowley

i pulled the 20 outa my project jeep and it had the kit from TSM..It did stop very well with 35's and manual brakes..They use an eldorado brake caliper with an intergrated parking brake lever..From the looks it reuses the stock e brake cables..I am pulling them off to put on my mud jeep,cuz I have fried too many shoes..About 2 sets a summer..

There was a guy on here that said he could make these brackets for a good price. I e-mailed back and forth with him and now I have lost his
e-mail

. I will try and find the thread again and see if I can find out who it was. I would like to get these brackets also!!!!!!

rednec03 · 04-13-2008, 09:33 AM

Will this fit 15in rims? I know the kit the Warn sells for rear discs says it requires a 16in rim. Any ideas?

jfwireless · 04-13-2008, 10:12 AM

I did a swap with Suzuki Samarai rotors and 300ZX calipers, emergency brake cables hooked right up. There is a thread on this subject, search and you will find my install and comments. I made a few changes to the original write up.

This was a significant brake upgrade to my 76 CJ, I wonder it those old drums ever worked at all.

Jim

ReconRabbit · 04-13-2008, 10:24 AM

Color me crazy but isn't something like 70% of the braking done by the front? I have discs front, rear drums, non power brakes and it stops descent with 33's on it. Why are you having to rebuild them all the time? Just curious, not trying to be defensive.

crusty75 · 04-13-2008, 03:20 PM

10 inch rear drums? Doesn't sound right. My 75 has 11 drums all the way around, work fine until water or mud, typical drums. If you have 10" drums, somebody did a very goofy brake switch, as 10" haven't been used since 1971 or so IIRC.

For nzirbel: Mud will tear up drums and shoes pretty fast, like sandpaper on steroids. Its a PITA, but you should always pull the drums and clean things out after a mud run. Not so much of an issue with discs. No mud wheelin, no problem, either type.

**BESRK** · 04-13-2008, 03:50 PM

In the late 70s (I think it was 76, 77, and 78), you would have 11" drums with the "big brake" (1.125" thick front disk) setup. Otherwise, I think they were 10.5"x1.5" drums out back with 7/8" thick front disks. From 79 (or maybe it was 80.. I forget), it was 10.5" drums out back and the smaller disks up front.

coxhaus · 04-15-2008, 10:59 AM

Well I bought the disc brake brackets from a guy on eBay. I am going to convert my rear drum brakes to disc using 1984 300zx calipers and 96 2 door Geo Tracker rotors(front). It turns out my pinion bearing is worn out and I need to rebuild my rear end. So I am going to change my gears from 3.55 to 3.73 and change my locrite to an ARB. I currently own an on board air compressor which I will try to incorporate. I hope it all works out ok and the 3.73 gears increase my gas mileage. I am going to wait to change the front axle until I decide if I like the new gear ratio.

illinicj · 04-15-2008, 06:15 PM

Why would lower gears increase your gas mileage? At the same wheel speed you engine will be turning faster. Lower gears means more power.

supraman1990 · 04-18-2008, 12:57 PM

Quote:

Originally Posted by illinicj

Why would lower gears increase your gas mileage? At the same wheel speed you engine will be turning faster. Lower gears means more power.

Not quite. If he has to gear down more to go up hills and such that isn't quite true. More gear means less gearing down in the tranny which keeps a lower RPM.

coxhaus · 05-06-2008, 08:53 PM

My new rear disc brakes on my Jeep are done. It stops great. I did not have to change the master cylinder or the proportioning brake value. The 373 gears seem to pull a little better on start up and between gears shifts. I have not checked gas mileage. I am not sure how far off the speedometer is now with the gear change. I will work on it.
I would recommend the disc brake change. I bought the brackets off eBay. Then I used 1984 300zx rear calibers and 1996 Geo 2 door rotors. You also need the rear short rubber brake lines and caliber brackets off the rear 300zx.
I had to change my lug bolts to longer ones to compensate for the rotors. Also one parking brake cable was too short.
I am going jeeping in July in Telluride Colorado. I need to change the gears in the front match to the new rear ones and rebuild the brakes. On to new projects.

rsg1963 · 08-27-2008, 08:08 PM

I have a 79' that had stock brakes (manual). They sucked with 33's. Before I did much else to the Jeep, I invested in hydraulic brakes:

http://www.hydratechbraking.com/products/jeepcj/

This is the hands-down, best thing I ever upgraded on any of my Jeeps and I've owned several over the last 25+ years.

I now have 35's and it still will send a passenger through the windshield if I so desire...LOL.

Did I mention that the brakes are still stock front & rear?

I will be upgrading to the rear disc soon also, but thought you all should remember that boost is more important than rotor size, or rotor count for stopping power. Also, there is a reserve built in, in case you are running a carb that stalls your motor out and you loose power while wheeling. After you use that, it's manual brakes.

Happy wheelin all! It's the 4-Dice trail for me this weekend...woot!