Park brake mounted on gearbox

Has anyone mounted the handbrake to the gearbox output shafts, specifically the Graziano? I started looking at the mounting location for the rear park brake caliper and realized it will require a lot of bracketry to get it to the correct location on the rotor. I am not using the factory kit, I have the Wilwood calipers 120-12069 & 120-12070.

MC4_Mechanical-lg.jpg


This caliper isn't designed to work with the Camaro rotors. The main issue is the thickness of the rear rotor. But the caliper can be easily modified to work if choosing to mount to the brake rotor.

To save unsprung weight I'm thinking of coming off the output of the Graziano and wondered if anyone has done this yet. The build manual gives an example on the Ricardo, but I don't know what rotor that is and the center section is custom. Also, my Graz is on backorder so I can't study it for feasibility.

Any pitfalls to watch out for would be appreciated too.

A.J.
 

Fran Hall RCR

GT40s Sponsor
We did this on some Ricardo transaxles years ago...it does require a lot of time consuming development and machining.
We used one rotor and one caliper only...

Mesa or P-nut may have pictures at hand
 
I wonder how big a caliper and rotor would need to be located inboard? This may sound crazy, but what about a mountain bike caliper and rotor? I have both sitting here as I upgraded to hydrolic brakes on it so it is basically free. That front brake can stop me going down hill at like 40mph with no issues at all so I am thinking holding a car sitting there might be fine. Now on a big hill, hmmmm, but we could make the mechanical advantage enough to hold? Just a thought?
 
My car (with a Ricardo) has this arrangement- a Wilwood rotor just 3/8" thick is more than enough. Easy to convert to electric parking brake as well, as mine also is.

For the Graziano, I'm guessing a similar arrangement to the build manual could be done, but you'd of course have to develop it yourself, including particularly the bracket. There are lots of calipers available, both cable and hydraulic, so the main issue would be routing cables and making the bracket.

I think a single caliper and rotor is sufficient, as one of the big rear tires being locked should hold any SLC from rolling, as long as there is traction. That would possibly simplify things as only one cable would have to be run, and there would be no need to keep two cables synchronized. Less effort on the handbrake lever as well, if you went manual.
 
Will, Can you link us to some pictures of your setup.

Also, I like your location. If OK I might have to come up and take a look at your car right before I jump into mine this summer.
 
I have a Graziano, but have the factory parking brake setup.

I did have a look today and don't think it would be difficult to mount a rotor to the right side CV and build a bracket for the caliper. The left side is lacking heavy enough mounting points for a caliper bracket.

I would suggest looking at the rotors we use on front-left of the sprint car. These are available in steel or aluminum. For most home shops, the aluminum ones will be MUCH easier to adapt. These rotors have 3 mount points so might work well - the CVs have 6 bolts.

Samples here: Front Brake Rotors - Circle Track and Oval Track Parts For Sprint Cars, Late Models, Hobby Stocks, Street Stocks, and Mini Stocks

We have spares of the rotors around so if you are interested in one I will pull one out and see how it works out size wise.

Don't be concerned about the rotor being aluminum. We can run 15 races on an aluminum rotor. They wear, but not significantly. We do use pads meant for aluminum - regular pads will be harder on it. We run wilwood calipers/pads so they may have AL friendly pads to fit your parking brake. But assuming you use it for parking and an emergency brake it should last forever regardless of pads. And if you have a real emergency and chew it up, it is cheap to replace.
 
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