here is the lastest project. 4 piston alumin calipers with 8" ventilated rotors to fit inside 10"wheels.
The calipers are machined from 6062 T6 aircraft grade billet. The pistons are 1 1/2" dia and made from 304 stainless. The brake pads are DB208 and work out to just under 20% of the disc face area.
The calipers have duraflex steel inserts between the calipers to hold the pads. The steel inserts are a stiffener and stop the caliper flex, which is a big problem with most after market calipers.
The whole lot is fitted to a std drum hub with a alumin adapter plate. The track is increased by 20mm per side, so either spacer drums or extended axles with std drums would need to be fitted to rear.
I still have to have these finally checked by the engineer, but the constuction exceeds the maximum requirements for stess and tortional loads. Inital pressure test had only .005" deflection at 3000 PSI.
If you want a set of them just PM. They are not cheap but still a lot cheaper than a set of std cooper S discs. ["bling"

at exra cost or see Gafmo, he loves polishing mini bits

]
Those blokes with machines to do a similar job I can give you pics and details of jigs and machining. Nothing hard ,just time consuming

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