Technical 55 Pontiac Treadle Vac residual valve

I recently acquired this '55 Safari. The car has the original Treadle Vac power brake system. I just installed a front disc brake kit on the car which led to my current situation...the calipers are sticking. I ruled out typical causes and determined there is a residual valve in the Treadle Vac master cylinder outlet which operates at a drum compatible pressure of around 10psi. I'm going to have to get the valve pressure off of the calipers or go back to square one. Has anyone removed or modified the pressure of this valve?

69719476_10219996812419450_1708246795861098496_n by Leevon posted Sep 11, 2019 at 8:10 PM

 

Here's what should help...….
www.pontiacsafari.com/55/ShopManual/5%20-%20Power%20Brakes-Bendix.pdf
KK

 

www.pontiacsafari.com/55/ShopManual/5%20-%20Power%20Brakes-Moraine.pdf

 

Sweet, thanks! Looks like it might be as simple as removing the cup and spring.

 

Standard drum brake residual pressure valve is 10 psi. Standard disc brake RPV is only 2 psi. But for a firewall mounted master cyl, you can get by with no RPV on disc brakes.