That calculator is kinda neat but it's making the same assumptions mine does and then some.

Keep in mind that mine was designed to give a quick and dirty idea of the size master cylinder you need for specific calipers and rotors. The rest of it was done just for grins.


There are some serious calculators out there that go much deeper than mine or the one above but I seriously doubt many people here will have the information required to make them work correctly. I know I don't have that kind of info on any of my setups.