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Brake systems
novacaine - 11/4/07 at 03:35 PM

friend of a friend is preping a 205 for rallying
ive been asked how to rig up a hydraulic handbrake, ive quickly scheched out a plan




now i cant see anything stopping the handbrake lever flying forward and smacking the driver/codriver/dashboard when the main brake pedal is pressed,

my question therefore is:

how can i rig up a hyrdaulc handbrake for this guy??

am i going to need an extra caliper on the rear wheel or will the system in the diagram above be good enough, i not too clued up about the operation of master cylinders so dnt make too many funny comments about my incompetence



cheers

Matt

[Edited on 11/4/07 by novacaine]


Mal - 11/4/07 at 03:55 PM

The hydraulic handbrake I had on my rally car some years ago was piped in a simpler way to your sketch.
As you probably know you need an aluminium master cylinder of the type with a bolt on reservior.
The pipe coming from the foot brake master cylinder to feed the rear brakes went into the port on the handbrake master cylinder where the reservoir would normally be bolted to. The pipe from the outlet port went to a tee piece feeding the rear wheels.
You are right in saying that the foot brake pressure is trying to push the piston out of the master cylinder. There is normally a circlip retaining the master cylind internals.
I had a flanged cap which went over the locating spigot on the end of the master cylinder. The cap was held in place by the same bolts that fix the matercylinder to the chassis bracket. You may also need a short spacer going into the bore of the cylinder to replace the circlip and transmit the load onto the cap.
It worked fine. You may need to retain the handbrake cable, set loose for MOT time.

HTH.
Mal


novacaine - 11/4/07 at 05:03 PM

thanks for that, cleared the design issue up for me


cheers

Matt