Rear Disc Conversion

well, not having done one myself this is only speculative. I would think by pulling all the necessary hardware from a wrecked Matrix or XRS and installing it on the rolla. Should be fairly easy and plug and play at the same time.
Junkyard would be best. You'd need the caliper mounting hardware, the calipers, I'd probably skip on the junkyard rotors and pads and buy those new, the spindles (maybe) and the brake distribution block (that is mounted on the firewall, if you trace the lines from the brake master cylinder you can't miss it).

That piece is especially critical. Drums and Discs require different pressure balancing and going right to rear disc brakes without changing that can cause lock-up of the rear brakes during what otherwise would be normal braking.
Donabed is 100% correct. Changing the brake proportioning valve is very important if you are going to change the car over to rear disc brakes.

I'm curious; why do you feel the need to change the rear brakes to disc brakes? Is there something wrong with the current brakes?


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the Disk/drum was the set up, people find rums older fashion while they do need to be visually inspected when doing the front pads. very difficult for people who never worked on one


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Most of the stopping is done through the front and prevention of fish tailing the rear with percentage. Never overlook your rear brakes when inspecting your fronts especially iay with disk setups
I'm curious; why do you feel the need to change the rear brakes to disc brakes? Is there something wrong with the current brakes?
Honestly It's more for the ascetics of it. ...drum brakes look tacky and cheap. And once I put some boost to the rolla it will be used on some scca track days at Nelson ledges as well as some solo2 autocross so the disc brakes on th back will only help me on those days
I read this about rear brakes somewhere. Rear disks Don't last as long because they get all the grime and stones and road stuff thrown at them from the fronts. Drums are protective of the brake shoes. How true this is I guess can be subjective but does makes sense to me. Anyhow, my car stops just fine so why fix what is not broke


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Why disk covers not dust cover you place on the outer side, behind the wheel. but of the Disk/rotor protects .

If your alloys are exposed, that may be cosmetics, but not all have very wide open allows. alot have stock and steel. so they hardly see the hardware.
Unless the car is pushed to the absolute limit and you're driving like a madman, you wont notice any difference between drum brakes vs disc brakes on the rear. I agree with acharleswhyte; if it's not broken, don't fix it.
Just doing a bit more research and pricing right now trying to see what size rotors would be on the rear to see if I can get crossdrilled and slotted rotors for the rear as well
The track is in Garrettsville ohio. And it's not a bad track, a bit more maintenance and it would be much better. It's no road Atlanta but it's nice no less
In most cases, cars with rear drums are not equipped with VSC or ABS.

The VSC wouldn't handle it, the ABS would, and it would decrease how effective the system is because it would constantly have to adjust the pressure in the rear brakes, even under light braking (not to mention you would have to deal with constant pedal pulsation).
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