It's up to the installer to set the "air gap", don't assume for one minute that's it's anywhere near correct, bench bleed your master, measure the depth of the bore's center to the mating surface of the master, measure the tip of the booster rod to the mating surface where the master's base will mount on the booster, do some basic math, adjust accordingly so that you have .020-.060 clearance in the bore for the pushrod to travel before it engages the master's piston