Got an AE93 corolla that I'm building up for motorsport. I want to install a hydraulic handbrake, but the cross braking setup of the AE93 master cylinder doesn't make this real easy.

I've heard the AE82 m/cyl has the two regular outputs and then goes to an external proportioning valve for the brake balance, rather than the integral setup of the AE93 I have.

So question is two fold, do the AE82 m/cyl's have just the two regular outputs ?

Will the AE82 m/cyl fit up to the AE92 booster ? Or will I need to swap the booster as well, or is there another option I'm not aware of ?

AE82 has internal valve.

Integral proportioning valve ? and not just a residual line pressure valve ?

I'd been told the AE82's used a regular m/cyl that was ported to a little manifold block that contained the proportioning valve and crossover drilling for diagonal braking.

i'm not brilliant with this stuff, but what you describes kinda sounds like a k series master cylinder set up

 

just my 2 cents

That's exactly the style of m/cyl I want, but I need it to bolt up to the AE92/3 Booster, which is where everything gets a bit muddy. I haven't heard of anyone else doing this yet.

I spoke to one at a rally with a coupe, they'd had a mechanic install a Hydraulic handbrake, but they hadn't thought it thru well enough and the car was looking a front and the opposite rear due to the diagonal braking. I haven't caught up with them since to find out how/if they've rectified it.

One option is to use a double m/cyl handbrake, but the piping gets VERY messy (and expensive in braid), besides which, one of the courses I want to race at has a clause in their supp regs that basically outlaws diagonal braking. Not sure why they've done that as CAMS don't have an issue with it, but them's the rules I've gotta play by.

Maybe I gotta call the local brake shop and see what the deal is, thought someone might have come across this before.

So after talking to the local brake shop dude, who did some hunting for us, there's apparently only one master cylinder that would bolt up and that's off a really old (GE?) Sigma. Not the answer I was hoping for.

He'd suggested ripping out all the proportioning valve cr@pola and then plumb is as per normal from there. Only problem being it would result in a system that if one circuit leaked, everything would be lost and I'd also end up with a lot of rear brake bias that I'd have to tune out. Neither scenario sounded real good to me.

So ripped the cylinder off the car, lucky as the rear circlip was broken in two :blinks:

After a bit of a measure up and a bit of think about things, I reckon I can machine a plug with a couple of o-rings that will stop all this diagonal braking nonsense and then the cylinder will operate as a regular m/cyl with pressure having to build in the front circuit before the rear's started to work.

However, since then a friend has told me that that parts for a true pedal box are not that dear, so if I can figure that little lot out, it might be the better way to go as tuning on the balance bar is usually better than tuning with a 'twiddle' proportioning valve in the rear line. But thought I'd update the thread for those searching in the future.

 

New topic over Here