What are the benefits of 2 piece rotors over 1 piece rotors?
(the NSX OEM rotors are 1 piece) A: Cast iron has optimum thermal properties — low deformability and good heat conductivity — as well as having process-related advantages, such as superior castability and machineability. It also has practical advantages, like good damping properties. Aluminum on the other hand is advantageously lightweight, being 2½ times less dense than cast iron, with the result that a 2 piece disc can be made between 15% and 20% lighter than its integral counterpart, depending on the application. This represents an important achievement, since car makers consider a 1 kg reduction in overall weight of the vehicle to be a real success, and even more so when “non-suspended” weight is removed, given the notably positive influence on comfort and driving precision. Unlike an integral disc, a 2 piece disc brake disc presents a symmetrical braking surface, favoring a more uniform temperature distribution when the brakes are applied; this means considerably less residual def
