[mickmate]

F=P/A Force = Pressure/Area
If you want more pressure you use a master with a smaller bore. The downside to that is it requires a longer stroke to move the volume to fill the calipers. Get as many measurements as you can off the length of pedal arms, pivots, master and slave sizes. I can send you an Excel spreadsheet I put together that does the math for you if you just put numbers in. There are some online calculators available also.