Quijoteus, the brake upgrade I did is better than stock but still has a bad fade problem after repeated stops from 100+mph (160+kph). I have the front struts and brakes from a 1980 510 and
the rear axle and brakes from a 1978 B-210. I also have steel braided lines on the front. I'm using Autozone lifetime warrantee pads so they could be part of the fade problem. I suspect
that a set of ducts to direct cooling air would help a lot. A2dubnut is a fan of 280Z vented rotors. I would suggest that as an option but check the spindle angle before using 280Z struts
or you might not get enough camber.