In the quest for more brake capacity (rules change which constrains our stopping distance at the event), we are doing a brake upgrade on the Mk I and Mk II. These are front rotors off a 1 liter road bike: 300mm dia, 5mm thx. Should have plenty of heat capacity.
Jeff hard at work:
The "after" shot with rotor mounted on the Mk I:
We have both caliper mounts fabbed, and even got one mounted on the Mk I. We took it around the block and had woefully poor braking ability. Now we're searching for a brake pad/compound which will work well with them beyond the hockey puck which the caliper came with.
Floating rotor... Good choice!
Can you start with bonded disc brake pads from a sedan, cut them to the correct profile on a bandsaw, then machine the lining to the correct thickness? I preume that your calipers are opposed piston calipers and mounted solid to the chassis..