The GiroDisc 2-piece rotor system is a direct replacement for the OE rotor, no modifications are necessary. The disc will bolt directly to the car and work with OE calipers perfectly. Once the Girodisc system is in place, simply replace the cast iron rotor ring when needed. The average Girodisc 2-piece rotor is approx 2kg lighter per rotor then the stock units. This reduction in rotational and unsprung weight allows for quicker acceleration and suspension response.
Please Note: These are lightweight two piece rotors that are made specifically to be used on the B5 S4 and C5 A6/Allroad with the OEM "18Z" Brembo 6 piston caliper found on the Porsche Cayenne, Audi Q7, and VW Touareg. The only modification required is some minor clearancing on the bottom of the upright. We can provide instructions and a video on how to do this. Other than that the discs will bolt directly to the car and work with the "18Z" calipers perfectly.