Before I ran into head gasket issue I have been working on big brake solution since this April.
I contemplated Speed Shop solution which is grafting on of C5 drum type parking brake. Tempting but I thought this to be overly complex. While surfing the web looking for a solution I ran into Revolution Brake website which advertised C4 rear big brake conversion using mechanical e-brakes. After a few telephone discussion with their rep, Kevin, I took a plunge.
This kit showed up with following major components:
As usual this did not turn out to be a straight bolt up conversion due to a few engineering issues.
Once the bracket is located to clear rotor (this dictates where the main caliper and e-brake caliper is located in in-out relative locations) main caliper was installed with no major issue. However, e-brake caliper was offset inboard by 3/16" and outer pad could not be installed.
Solution was to shave outboard shoes by 3/16" and have a shim cut out of 3/16" aluminum to be used as shims for the inboard.
Problem: Factory cable sheathing was too short due to new sheathing mounting on the bracket.
Solution: "L" shaped brackets under the car where the other end of sheathings clip to was cut and shortened by 1-1/4".
Problem: Factory e-parking cable at the wheel side is a rectangular casting with a rectagular hole designed to slip over parking brake lever. New e-brake caliper is actuated via lever with a hole designed to accept clevis.
Solution: Bought 2 additional clevises and using M6 thread clevises were attached back to back so that one end would connect to e-brake lever and the other end would connect to rectangular cable termination.
This conversion took a while and some sorting out but final result works like a charm!
Ans "yes!" this set up with 13" rotor will clear factory A molds - Jim and I confirmed it by mounting a factory A molds.
Once my motor rebuild is complete I will convert the front to 14" Wilwood 2 piece rotors and 6 piston Superlites.
After that I will replace rear rotors also with 2 piece 13" Wilwood rotors.