Flywheel/Clutch ideas

Here's an estimation of the minimum clutch clamp pressure required for typical 10.4" disc to hold 600ft/lbs...
...organic- 3056lbs
...carbon Kevlar/ceramic DF- 2429lbs
...organic/puck style iron DF- 2542lbs
...ceramic- 2048lbs
...puck style iron- 2077lbs
...full face iron- 2091lbs

You also have to take into consideration that a B&B PP's coil springs will lose clamp pressure as the disc wears, so clamp pressure must be even higher when the disc is new just to make sure you still have enough clamp to hold 600 when the disc is near the end of it's life. The result is that your clutch pedal will be it's stiffest when the disc is new, and easiest to push when the disc is worn out.

With a diaphragm PP, it's Belleville spring design typically gains clamp pressure as the disc starts to wear, then at about the mid-point in disc wear, the trend reverses and starts to gradually lose clamp pressure. At the end of the disc's life, clamp will be back to about where it started. The result is that your clutch pedal will be easiest to push when the disc is new and also when it's worn out, but even at the mid-point of the disc's life when pedal effort will be at it's stiffest, it will still be easier to push than an equivalent B&B PP with a new disc. Downside is the typical diaphragm doesn't like engine braking, thin straps between the cover and pressure ring are easy to bend when they see reverse torque during clutch engagement.

Grant