hello everyone, i have a 1982 chev.c10. 350, automatic, with a mild hi-lift cam.my problem is the brake pedal goes to the floor at idle if you apply light but steady pressure.you can release the pedal and re-apply pressure (pump one time) and you have a full and firm pedal. i suspect i need to add a vacuum reserve tank for the booster but don`t quite know how to go about it without a lot of trial and error. thanks in advance to anyone who responds.
typicaly a lack of vac from a cam or leak will make your pedal firmer. your master is probably going bad or you have a leaking wheel cylinder.
As said by the first post leaking wheel cylinder or leaky lines caliper valve at the front, if all is ok. Then I would try bleeding brakes a few extra times . To make sure all the air is out.