Sneak peak of the next big upgrade. The car currently has F/M/J body discs on the front. I bought these gen 1 Viper rotors years ago to use the Dr Diff kit, but they used a relatively small rotor. I know he has kits with bigger rotors now, but I decided to make my own big brake kit. This is the gen 1 Viper caliper, modern mustang 13.25β rotor, and a F/M/J body rotor with the brake surface turned off. I did some measuring of this caliper to determine what the largest diameter rotor it could accommodate. Turns out 13-13.25 is damn near perfect. The pad surface is the exact same height as the rotor. Itβs almost like they were made for each other.