The Ford Barn

Bruce Lancaster · 09-26-2014, 10:13 AM

On the brake disc...as RPM goes up (actually starting right off idle) the advance starts to move and loads the brake disc in one direction...in retarded position the slots are not being pushed forward, so piston drag holding disc back stabilizes it. While driving car is almost entirely above RPM where advance starts, and action at that disc will always be some combination of centrifugal push and restraint on same push by brake, with the brake action probably being very slight most of the time with screw way out.
It was much more important in prewar low octane days, and also with lazy pre-automatic trans drivers lugging the car to avoid the effort of shifting.

09-26-2014, 10:13 AM	#23
Bruce Lancaster Member Emeritus Join Date: May 2010 Location: Madison, NJ Posts: 5,230	Re: vacuum advance disabled On the brake disc...as RPM goes up (actually starting right off idle) the advance starts to move and loads the brake disc in one direction...in retarded position the slots are not being pushed forward, so piston drag holding disc back stabilizes it. While driving car is almost entirely above RPM where advance starts, and action at that disc will always be some combination of centrifugal push and restraint on same push by brake, with the brake action probably being very slight most of the time with screw way out. It was much more important in prewar low octane days, and also with lazy pre-automatic trans drivers lugging the car to avoid the effort of shifting.