Well, I've done complete brake systems for years but I'm dealing with an issue on the '32 while switching out from drum to disc. Using a Wilwood four piston race brake setup(new)on the front with stock Ford drum rears. Ford style disc/drum master cylinder(new) and discs are plumbed to the large reservoir with an inline 2# residual valve. Pedal is spring loaded up with 1/2" free travel. Rears have an adjustable proportioning valve inline. The brakes bleed fine and pedal is good but the discs do not release fully and are definitely too tight to drive without overheating . I removed the residual valve but no change. The lines were blown thru with air pressure to clear them of old fluid before the new parts were bled. I can crack the line at the calipers (either side), the master cylinder, any line connection or brake hose and the pressure releases allowing the rotors to freewheel. My gut feeling is the master cylinder is not accepting the fluid back into the reservoir. Any other ideas I'm overlooking?