Rear brake compatability??

[Hocrest]

I need to replace the rear drums on my brat. I am planning on looking for a set of disks off of a turbo. If I can't find a good set, do I need to use EA81 drums or can I get a set of drums off of an EA82 also??

 

I'm guessing I can since that what the disks are coming from, but thought I'd ask to be sure.

 

If I do get the drums off of an EA82 what do I need to grab at the yard? Backing plate? Lines? anything else other than the drum assembly itself?

[GLCraig]

If I remember right you'll need drums from an EA81, there maybe a difference in diameter. Also try and get drums from an 83 or later, they're the ones that are least likely to warp.

[GeneralDisorder]

You should be able to bolt on the entire drum assembly from an EA82 if you want. All the EA81/EA82 rear brake systems bolt to the control arms the same way - you just have to monkey with the hard/soft lines to get them properly routed. I *think* some of the later EA82 drum systems were also self adjusting.... could be wrong on that, but I swear I've seen some that were. I wouldn't bet on the drums fitting in place of an EA81 drum tho - being heavier, the EA82's were probably equiped with larger drums in the rear just as they were equiped with larger discs in the front.

 

I have some extra EA81 drums laying around if you get desperate - several sets actually. At least two sets have the rubber covers for the adjusters!

 

GD

[edrach]

If at all possible, just find a set of disk brakes for it. Take everything: backing plate, caliper, rotor and hub. I even take the brake lines and all hardware just to be sure. An easy conversion and worth every penny you spend on it. Also, take a rust penetrant to the yard when you go to help remove the backing plate.

[MilesFox]

the ea82 drum will fit if you swap over the backing plate and all.

 

in fact, you can swap an entire trailing arm/brake assembly from an ea82 with slight trimming. the axle nuts and shaft splines will all be the same between either.

[Vince]

wouldn't you need to change out the proportioning valve on a drum to disc brake swap? If you don't your brakes would not work right for example the car would nose dive and the front brakes would lock up on normal braking. My brakes teacher said you can get a manual adjusting combination valve and youi could play with the settings until your car stops right.

[MorganM]

wouldn't you need to change out the proportioning valve on a drum to disc brake swap? If you don't your brakes would not work right for example the car would nose dive and the front brakes would lock up on normal braking. My brakes teacher said you can get a manual adjusting combination valve and youi could play with the settings until your car stops right.

Yep; either re route your lines around it to bypass the porportioning valve or remove it entirely and re run the lines. It will certainly work if you dont do anything with the lines and porportioning valve but as you stated it wont work like a real 4 wheel disc brake system.

 

Those manual valves are pretty trick. Can get universal ones from Sumit for about $60 each. I was gonna get 2 for my rear drums to put in line cuz I had to run al new lines and bypassed the porportioning valve. Instead I just went and got some rear discs off a turbo wagon

[GeneralDisorder]

wouldn't you need to change out the proportioning valve on a drum to disc brake swap? If you don't your brakes would not work right for example the car would nose dive and the front brakes would lock up on normal braking. My brakes teacher said you can get a manual adjusting combination valve and youi could play with the settings until your car stops right.

This has been discussed at length in the past, and the consensus is that it's not needed on the EA81's. EA81's do not have proportioning valves anyway, and adding them does not seem to be needed for a disc swap.

 

Swapping over to the disc's on the EA81's has been done by many, many folks (including myself), and no issues have ever been noted by anyone who has actually done it. Normal braking is not affected, and with the rear discs on a lifted rig, you can lock up all 4 wheels on dry pavement easily.

 

GD