Topic: 1966 gt rear brake proportioning valve adjustment

[socalgt]

I understand this a trial and error adjustment.  Am I correct that you want pressure to the rear wheels so that they do not lock up before the fronts? ( actually i've never had front brakes lock up in a 1965/66 GT front disc brake setup)  Do I need to adjust the valve until the rear lock up and then back it off?

Thanks for any suggestions......

[Bob Gaines]

I understand this a trial and error adjustment.  Am I correct that you want pressure to the rear wheels so that they do not lock up before the fronts? ( actually i've never had front brakes lock up in a 1965/66 GT front disc brake setup)  Do I need to adjust the valve until the rear lock up and then back it off?

Thanks for any suggestions......

You are correct that you want to adjust the pressure to the rear wheels so that they do not lock up before the fronts? If you can't lock up the front brakes then that is a separate problem.

[socalgt]

Guess I haven't tried a high enough speed to see if the fronts lock up......I'll do some experimenting in a parking lot.....

Thanks

[sgl66]

Guess I haven't tried a high enough speed to see if the fronts lock up......I'll do some experimenting in a parking lot.....

Thanks

I recall others posting that a starting point is to have 11 threads exposed on the prop valve. Another tip I read is if possible to try and drive and lock up the wheels on grass or a dirt road.

[Brian Conway]

Ditto on the eleven threads showing.  I run the OE GT brake system and very seldom have locked up the front discs.  Brian

[Bob Gaines]

I have several NOS units and multiple unrestored cores. 11 threads is typical on all the ones I have. Apparently that was the default K/H factory setting . 65/6 Shelby's were adjusted different from K/H because of the 2 1/2 brake