Brake Questions

Brake Questions - Help

'69 Fender tag may indicate if it was always disc brake car. Someone else here will know that off the top of their head.

I can tell you the pictures so far show a factory setup.

dennisonwj said
1) How would I know if the front disk brakes were factory installed or after-market? One of the pictures below shows the caliper and you can see "A71312" on the passenger side one.

Those pictured are the 4 piston fixed calipers made by kelsey Hayes and used with only a slight variation through the '72 model year.

dennisonwj said
2) Is the picture below a proportioning valve or a distribution block? I am concerned someone just threw on front disc brakes and did not install a proportioning valve nor install the correct master cylinder.

It is the correct distribution block for '69. The proportioning valve will be a little further back on the frame rail.

dennisonwj said
3) The master cylinder is manual and there is a "20872" stamped in the rubber seal gasket and made in "U.S.A." BUT both chambers are the same size/volume like it is for a 4 wheel drum car. Again, I am concerned someone bush-leagued the brakes and did not install a proportioning valve the correct MC.

Your concern is well placed. However the good? news is that most replacement master cylinders from the big rebuilders (like Cardone) use the master cylinder you have. They convert it to disk/drum use by removing the residual valve for the front brakes. It will work fine, but of course in an ideal world the disks should have a larger reservior. I finally bought a correct mc this past year from Kanter Auto.

dennisonwj said
) The vehicle does not seem to lock up the rear wheels when braking and without a proportioning valve that would happen, right?

The other way around. Proportioning valve reduces pressure to the rear to reduce lock up. Drums are self energizing and need less pressure compared to disks.