I have a dirt track car based on a G-Body platform. We are allowed to run disc rear brakes. We are not allowed to use adjustable proportioning valves and all 4 brakes must be in working order. Right now I have a master cylinder and rear wheel cylinders off a manual brake S-10. My goal is to go from like 70% front brake or whatever factory settings are at to more like 50-50. I can get a rear disc brake setup and get some oversize calipers or heavy duty pads and get rear brake % up. But if I do that I think I have to make changes to the proportioning valve? Because it will have a residual valve somewhere (in master cylinder or proportioning valve, not sure which one) with 10 PSI to overcome the springs in the drums whereas the discs only need 2 PSI. So if I run disc rears I'm not sure what else I should change? I'd like to keep an aluminum master cylinder (has to be OEM). I was actually in the process of taking the proportioning valve off and just putting tee-fittings and couplers there to replace it, and possibly just leave the rear drums alone, to see if that helps. But I'm not sure if that would hurt me if the proportioning valve also has that 10 PSI residual valve in it. I can move to rear discs if I need to. Just looking for suggestions from someone that has done this already. I don't want to make matters worse by having my brakes locked up. Should I be OK taking the proportioning valve off and putting disc brakes in the rear? Or will the manual master cylinder cause problems because it will want to hold 10 psi at all times to the rear?
EDIT::: I just found out the proportioning valve will also delay braking to the front momentarily to prevent nose dive. Seems to me this is also a desirable trait. So maybe I want to keep a combo valve and drum brakes (drum brakes require less pressure to work as well supposedly), but put a different OEM proportioning valve in or modify this one?
EDIT::: I just found out the proportioning valve will also delay braking to the front momentarily to prevent nose dive. Seems to me this is also a desirable trait. So maybe I want to keep a combo valve and drum brakes (drum brakes require less pressure to work as well supposedly), but put a different OEM proportioning valve in or modify this one?
