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Über Genius
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Just Some Dude in Jersey
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Discussion Starter #122
Sure, I'll give it a go.

I don't remember exactly how it all played out, but it seems that I copied Dieter's set up linked earlier in this thread. I'm not sure about the rotor thing, though. I do know that I got rotors that had 4x4.25" spacing and that I used a drill and a digital caliper/micrometer to hog the holes a little closer to the center so that they measured 4x100mm.

I'm pretty sure as I type this that the pads stop about 1/8" from the outer edge of the rotors.

I made a tracing of my brackets, which have holes drilled for the early c-clip axles. Two bolt holes are closer together than on the later style axles. If you're thinking of doing this mod to a c-clip axle, I could send you a copy.
 

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Über Genius
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Sure, I'll give it a go.

I don't remember exactly how it all played out, but it seems that I copied Dieter's set up linked earlier in this thread. I'm not sure about the rotor thing, though. I do know that I got rotors that had 4x4.25" spacing and that I used a drill and a digital caliper/micrometer to hog the holes a little closer to the center so that they measured 4x100mm.

I'm pretty sure as I type this that the pads stop about 1/8" from the outer edge of the rotors.

I made a tracing of my brackets, which have holes drilled for the early c-clip axles. Two bolt holes are closer together than on the later style axles. If you're thinking of doing this mod to a c-clip axle, I could send you a copy.
It certainly wouldn't hurt to have a copy of that tracing but I'm getting ready to have a mock up bracket 3d printed just to be sure of the placement. That 1/8 measurement seems like it would be about right. It splits the difference of the diameter variation.

My plan for the rotors is to take the rotor part number you gave and then drill a second set of holes at 4x100 since my drill press is super accurate for drilling but hates to do any milling.

I have both types of axles so I have to make both types of brackets. Once I get the first one 3d printed then I can work from that to get the newer style done.

Thanks for your help.
 

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Just Some Dude in Jersey
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Discussion Starter #124
It's darn near impossible to see the brake pads on these brakes, but, judging by the wear patterns on the rotor from my 4 block ride, the pads stop 1/16" from the edge of the rotor and 1/8" from the "hat" at the center of the rotor. The calipers themselves have 1/8" of clearance from the outer edge of the rotor:






 

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Über Genius
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Those pictures work perfect. Thanks!
 

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Scheibenbremse Kit Bremse Hinterachse Kadett C Manta Ascona A B CIH 14" Brake | eBay

Disk brake system for the rear axle of the models Kadett C, Manta A and B, Ascona A + B fit for the models record C, D and E this even partially, if bolt pattern 4 x 100.
In this brake system is not revamped (PCD, hub bore) used discs, but the discs are on sale so that is off the shelf. The calipers are from the VW family.
This disc brake system is suitable from 14 "rims or 13" BBS e30 with Flat rims.


One (1) hour to auction end.
Current price EUR 202 ($269.65 USA) plus EUR 90 ($120.14 USA) shipping.

Final price EUR 216 ($288.34 USA) plus EUR 90 ($120.14 USA) shipping.
Hi, I know has passed only 7 years since this post...lol. The matter is I bought that kit and came without instructions... I got few pictures but doesnt show too much. If you know, could you advice me how to installed properly? I am not a clue where should be two of the three plates (the small L and the square plate.... not idea at all)
Thanks in advance
 

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Check out this thread, maybe it inspires you: has anyone put discs on the rear

Then, ask yourself, if you lack the knowledge to put pre-fabricated parts together, is this the right adventure for you? I'm not the judge about your knowledge and abilities, but think about, these are the brakes of your car and you have 8 lives less than any of my cats.

Dieter

426690
 

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Check out this thread, maybe it inspires you: has anyone put discs on the rear

Then, ask yourself, if you lack the knowledge to put pre-fabricated parts together, is this the right adventure for you? I'm not the judge about your knowledge and abilities, but think about, these are the brakes of your car and you have 8 lives less than any of my cats.

Dieter

Cheers for the advice Dieter. Just I want to collect all info possible before start. No risk, no glory...
 

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Hi, I know has passed only 7 years since this post...lol. The matter is I bought that kit and came without instructions... I got few pictures but doesnt show too much. If you know, could you advice me how to installed properly? I am not a clue where should be two of the three plates (the small L and the square plate.... not idea at all)
Thanks in advance
We are going to need pictures in order to help you!
 
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We are going to need pictures in order to help you!
Thanks for your replay. Please see the picture attached.We could say that we have 3 kind of attachment plates per side; 1 Big L, 1 Smaller L and 1 square. I think the Big L is going to be attached in the back of the shaft as the second and third picture shows. But what about the small L and the square plate?
** I think the steel bearing retainer should stay and the square plate should help to do a doubler for the backing plate.But, what about the small L plate? and the cover shaft plate should be discarded (last picture)?
Thanks
 

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Just Some Dude in Jersey
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Discussion Starter #131
The small L's and the squares are thin and have no provision for mounting the caliper, so they must be either spacers or reinforcers. I didn't need spacers or reinforcement on my set up. I suggest installing the big L's to the axle as shown, then mount the brakes to them. Install the rotors and see how things line up. He may have designed his kits for guys to use other calipers, like Willwoods, and maybe they need the spacers.
 

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The small L's and the squares are thin and have no provision for mounting the caliper, so they must be either spacers or reinforcers. I didn't need spacers or reinforcement on my set up. I suggest installing the big L's to the axle as shown, then mount the brakes to them. Install the rotors and see how things line up. He may have designed his kits for guys to use other calipers, like Willwoods, and maybe they need the spacers.
Thank you very much, it makes sense. I just wanted to have a good plan before being in the middle of work with a problem due to poor organisation.
 

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Just Some Dude in Jersey
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Discussion Starter #133
I don't see a proportioning valve in your pics. You will almost certainly need one to reduce the hydraulic pressure to the rear disc brakes by about HALF. Without one, the rear brakes will lock up even under light braking. Our cars are too light back there. Our cars need rear disc brakes like they need chicken wings: They don't, it's massive overkill. Unless you're racing, rear disc brakes are mainly just a cool project. At best, expect only 10% better braking.

GT's were one of the fastest stopping cars in tests back in the day. I've always thought that that was why so many GT's got rear-ended, other cars couldn't stop as quick as ours. :)
 

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I don't see a proportioning valve in your pics. You will almost certainly need one to reduce the hydraulic pressure to the rear disc brakes by about HALF. Without one, the rear brakes will lock up even under light braking. Our cars are too light back there. Our cars need rear disc brakes like they need chicken wings: They don't, it's massive overkill. Unless you're racing, rear disc brakes are mainly just a cool project. At best, expect only 10% better braking.

GT's were one of the fastest stopping cars in tests back in the day. I've always thought that that was why so many GT's got rear-ended, other cars couldn't stop as quick as ours. :)
A very good point. I am looking the best place to fit the proportioning valve. My engine bay is not like yours... mine is plenty of gaps 😁... did you removed your residual valve? the one that is coming originally for the rear drums that is attached in the brake manifold attached to the servo brake?

Thanks once again.
 

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Just Some Dude in Jersey
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Discussion Starter #135
I don't recall ever seeing something called a residual valve on our master cylinders, the lines just go straight to the MC. I'm using the big Honda MC that OGTS sells, BMW vented rotor brakes in the front, and the VW rears mentioned in this thread. My adjustable proportioning valve is mounted in the center of the car in front of the chassis bracket where the rear rubber flex hose attaches.
FYI about that:
If you like to use a pump up Power Bleeder to bleed your brakes, it will no longer work when doing your rear brakes if you have a proportioning valve.
I don't know why, all I know is that I have to have someone pump the pedal when I bleed the rear brakes now.
 

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I don't recall ever seeing something called a residual valve on our master cylinders, the lines just go straight to the MC. I'm using the big Honda MC that OGTS sells, BMW vented rotor brakes in the front, and the VW rears mentioned in this thread. My adjustable proportioning valve is mounted in the center of the car in front of the chassis bracket where the rear rubber flex hose attaches.
FYI about that:
If you like to use a pump up Power Bleeder to bleed your brakes, it will no longer work when doing your rear brakes if you have a proportioning valve.
I don't know why, all I know is that I have to have someone pump the pedal when I bleed the rear brakes now.
Thanks, I think this is my residual valve (see picture) otherwise if someone know it, please dont hesitate to let me know. I got your point, now I have to bleed the brakes like the old style, pump & hold .....
residual valve.jpg
 
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