Cant answer your question even though I am a degreed mechanical engineer, because it is the ratio, or fractional difference if you like fractions better than ratios, that determines force difference. It is the difference in size that determines what happens.Thanks for the reply, but never took Algebra. Just need to know if pressure is increased or decreased with different size bores in the MC using front disk & rear drums.
You got half of it right. The volume of fluid moved is greater with a larger bore, but the pressure generated is the same regardless of bore diameter. That is a function of pedal pressure. Resistance or effort goes up with an increase in bore size which is why most manual brakes have a small bore and power assisted brakes have a larger bore size.To sum up, smaller bore makes more pressure, but moves less fluid.