Rear Disc Conversion

[ace_1984]

Wondering if anyone here has done this with any success or know of a kit that's available or what parts I'd need to do so.

 

[echarleswhyte]

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.

 

[IFMJohn]

From what I have read, it is a Direct swap with no real issues from a xrs/matrix.

 

[Donabed Kopoian]

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.

 

[Scott O'Kashan]

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?

 

[fishycomics]

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

 

[Donabed Kopoian]

More aftermarket for rear disc brakes as well. Drums are pretty much dead to performance braking companies.

 

[fishycomics]

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

 

[ace_1984]

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

 

[echarleswhyte]

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

 

[Donabed Kopoian]

Meh. I've had several cars with rear disc and never seen evidence of stone damage or anything of the sort. The tires cover the rotors.

 

[fishycomics]

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.

 

[Scott O'Kashan]

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.

 

[Scott O'Kashan]

ace 1984 - So how are you making out with this?

 

[ace_1984]

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

 

[Scott O'Kashan]

Are you racing the car or something?

 

[ace_1984]

Not racing so to speak but I do intend on doing some scca solo 2 autocross as well as some track days at Nelson Ledges

 

[Donabed Kopoian]

Nelson Ledges? Where is that track at? Any good?

 

[ace_1984]

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

 

[Scott O'Kashan]

If the need for upgrading the brakes is present, then upgrading the tires and the suspension is also a wise move.

 

[Scout706]

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. . .

wouldn't the VSC handle this?

 

[Donabed Kopoian]

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).

 

[Scout706]

ESC mandatory in all US sold cars starting 2012 model year. OP didn't mention model year.

 

[Donabed Kopoian]

Regardless, it is mandatory to change the brake pressure proportioning valve.

 

[SuperchargedMR2]

Regardless, it is mandatory to change the brake pressure proportioning valve.

There is no brake proportioning valve with ABS equipped cars. I'm doing this drum to disc conversion on my 2009 Corolla S Turbo 5MT. I'm also installing a Ceika BBK on the front.