manual proportioning valve??

[Zignas X]

Hey guys. I was wondering if i can use a manual proportioning valve by itself or do i need to have a distributing block for my brakes??

 

[2+2GT]

The proportioning valve and distribution block have totally different functions, and operate independently. I don't see how you could avoid having a distribution block. The master cylinder, even if you use a dual bowl type, will need to feed both front wheels, so you need at least a "T" fitting. The rear brakes have their own "T" fitting, on the axle end of the hose. The proportioning valve is needed only when you have disc front brakes and drum rear brakes, since disc brakes require much higher, about double, the line pressure to operate. Without it, the rear brakes would lock before the front brakes began to work.

 

[mtaqua]

I think the dist block he is referencing is the stock one, and I think on some they have a proportioning function built into them (70/30). I have t-fittings splitting the lines, and manual prop valve on mine. I've got 4 wheel disc, allows me to control the bias to the rear brakes(runners and large rear tires). you can run one without the stock dist block. I do think stock dist blocks (combination block) have one way valves or something that will stop all the fluid from coming out if you develop a hole in the front or rear brakes (allowing the opposite system to still work; i.e. rear gets a leak, front still works). I did not use one, so I loose all of my brakes if I get a big enough leak anywhere in the system. I did install a fox body style e-brake and it will stop the car.

 

[JonK]

If you are looking to go aftermarket you can get a combination dist. valve/prop. valve, I'm using one on my '67 to save space, lines and have adjustability. The 2 most common are by SSBC/Summit knockoff and Wilwood:
http://www.ssbrakes.com/commerce/detail/index.cfm?nPID=8862
http://www.summitracing.com/parts/SUM-G3910/
http://www.summitracing.com/parts/WIL-260-11179/

Jon