I intend to upgrade the brakes on my S3, Brembos on the front and I want to upgrade the rear. I have got a set of Brembo rear callipers off my Mitsubishi Evo and wondered if I could get them to fit! In theory can you get any caliper to fit any car provided you manufactured a custom mounting bracket? Does anyone know the rear disc size on the S3? And the distance between centres of the mounting holes on the S3's existing rear callipers?