The difference in size between the size of the wheel cylinders and the master cylinder is just like changing gears. A bigger master cylinder will require less foot travel but a harder push from your foot. Like being in high gear.
In retro spec if you change to a smaller master cylinder wheel cylinders remaining the same, more travel but less force is required.
It is fairly simple to figure out what you need to make the swap first figure out the volume of the stock master. Then the difference in volume between combined rear and combined front wheel cylinders.
This difference is the front to rear hydraulic bias you then need a master cylinder the same total volume as the original with the front to rear bias of your wheel cylinders and that is that in a nut shell.
