There's a lot that goes into proper brake pressure and most of it's math. Here is a good article from Joe's Racing that explains how to determine caliper area and pressure with different bore masters. I have a 68 Mustang and use a master from an 85 Fox body called a step bore or fast fill master. It has two piston diameters and gives manual foot pedal feel with power brake stopping power. Difficult to bleed.
https://www.joesracing.com/master-cylinder-math/