These GiroDisc 2-piece rotors are a direct replacement for the front rotors on the BMW G80 M3, G82/83 M4, and G87 M2 without factory carbon ceramic brakes. These fully-floating assemblies help shed unsprung weight and rotating mass from the front axle of the vehicle.
The rotor rings are machined from a proprietary casting made of high-carbon iron formulated to GiroDisc's specifications. This superior metallurgy results in a rotor that better withstands hard use, and the curved vanes act as a centrifugal pump pulling air in through the hub to cool the discs. The 2-piece design has a reusable hat which can be installed onto new rings when they need to be replaced.
All major components including the hats, rotor rings, and drive pins are manufactured in-house at our facility in Bellingham, WA from domestically-sourced materials. The hat is made from 6061-T6 aluminum and coated in a black anodize finish. The drive pins are made from a high-strength steel alloy and cadmium-plated for corrosion resistance. All rotors are assembled with spring clips and spring washers for race-ready float while also being street-friendly with no noise from loose hardware.
Outer diameter: 380mm
Thickness: 36mm
Minimum thickness: 34mm
Weight: 28.2 lbs per rotor assembly
Vane count: 72 curved vanes (vs 30 vanes in factory discs)
Replacement rings: D1-282
We recommend replacing the rings when they reach minimum thickness or if a crack forms leading to the edge of the ring.
