Changing to disc brakes, do i need?

[KPoole9008]

I am in the process of changing rearends. The old one had drum brakes and the new one has disc. I used a 10 lb residual valve and a proportioning valve for the drum setup and a 2lb valve on the front. The mastercylinder is mounted under the floor. Now that I have disc all the way around,do I still need the residual and proportiopning valves ?

 

[putz]

I am in the process of changing rearends. The old one had drum brakes and the new one has disc. I used a 10 lb residual valve and a proportioning valve for the drum setup and a 2lb valve on the front. The mastercylinder is mounted under the floor. Now that I have disc all the way around,do I still need the residual and proportiopning valves ?

You still need both only use a 2 lb for the rear disc also. Check the proportioning valve adjustment after the install on gravel at low speed if possible. The residual valves are for keeping pressure in the lines to help with pedal travel. There are quite a few people that don't use them at all but proportioning valve you definately need due to stopping tires under power compared to tires that aren't.