Brake pedal travel

67Dart273 said
You can lose "some" pedal just in the drums. When you machine drums oversize, the shoes are "too small" diametrically. They can actually flex in the drum, or at least don't fit "soldidly" and act as to "soak up" pedal travel. You can sometimes eliminate this while diagnosing by adjusting them up TIGHT. If the pedal seems firmer you are on the right track. Obviously you don't move or drive the car while doing this.. Weak hoses can expand, as well

I test the drums being the problem by simply setting the E brake and see how it feels on the pedal.:D
This way you don't have to adjust and readjust the brake shoes in the drums.

Lucas said
If you are having excessive pedal travel related to the fronts after the rear drums are adjusted a 2 psi residual pressure valve can be fitted at each front brake line inline.
If it’s a piston retracting to far back for the given master cylinder size then this will help.
This will also help with any knock back that may be experienced while driving.

This is a good bit of info.
I recently swapped a 1959 Ranchero with manual drums over to power and the residual valves solved a first step low pedal. (pedal was much higher if you pushed it twice)
I put one between the master and distribution block for the fronts and rears both so I only needed one for both fronts. (of course I used 10lb for drums)
Now the brakes are right there on the first step of the pedal.