I recently installed front and rear disc brakes on my 67 Camaro SS and after repeatedly bleeding the system I still have a soft or spongy pedal. this is a power assist system. any help would be greatly appreaciated.
Did you change the master cylinder? If so did you bench bleed it? Did you change the proportioning valve? How did you bleed the brakes? I used a Mighty Vac and start at the right rear and keep the master cylinder topped off.
The top hole is for manual brakes and the pin needs to have the return spring connected from the top hole to column support.
The bottom hole is for power brakes and you can get away with not using the return spring with the booster back pressure.