Rally rear disc conversion

[AndySi]

Hi
just looking for advice on rear disc brake conversion for my Cortina that I use for rallying. I bought a Retroford rear disc conversion kit and whilst the rear discs work perfectly well with the foot brake. I can’t get it to lock up with the hydrolic handbrake. On reflection the kit uses Honda Jazz callipers and I just don’t think they are man enough for the job. I’ve looked at the Sierra Cosworth conversion but likewise I hear they aren’t brilliant for handbraking the car around. I used XR3 callipers back in the 80s on my Escort rally car but these don’t seem to be available. I see Hispec do a twin pot calliper kit via Burtons, but before I spend any more money. Any advice on a good alternative would be greatly appreciated.

[Forest_rallying]

Hi
just looking for advice on rear disc brake conversion for my Cortina that I use for rallying. I bought a Retroford rear disc conversion kit and whilst the rear discs work perfectly well with the foot brake. I can’t get it to lock up with the hydrolic handbrake. On reflection the kit uses Honda Jazz callipers and I just don’t think they are man enough for the job. I’ve looked at the Sierra Cosworth conversion but likewise I hear they aren’t brilliant for handbraking the car around. I used XR3 callipers back in the 80s on my Escort rally car but these don’t seem to be available. I see Hispec do a twin pot calliper kit via Burtons, but before I spend any more money. Any advice on a good alternative would be greatly appreciated.

Back in the day we used Chrysler 180 rear brake callipers which were perfect because they had a handbrake cable set up to comply with Regs, you could even get Mintex 171 pads for them, however that was over forty years ago.

The XR3 front brake callipers are okay but you’d need to fabricate a dummy cable setup and use an inline pressure reduction valve as well. The only comment I can make on a Jazz is they never appear to go fast enough to need brakes. Have you looked at VW rear callipers like are fitted to the Golf, they seem a nice alloy calliper.

[Mkdu]

I found in germany new XR3 ones, just try to find the carrier with an old pairs !
I used sierra ones, but struggle with handbrake stuff what I don't need.
I use 2 pots Hispec for just for handbrake. I don't like the pedal movement when you brake and use handbrake during braking phase

[AndySi]

I found in germany new XR3 ones, just try to find the carrier with an old pairs !
I used sierra ones, but struggle with handbrake stuff what I don't need.
I use 2 pots Hispec for just for handbrake. I don't like the pedal movement when you brake and use handbrake during breaking phase

Thank you I have got some XR3 calipers and hope these do the job. I think I will need to dial them back on the bias peddle box to get the foot brake balance right though.

[Mkdu]

I used those 2 weeks ago on a track, no issue, it seems to work. I put more on front when rear move too much on heavy brakes.
I didn't check the pads since then, all was new, discs also.
I put new sliders also as well because of 2nd hand carriers.