I've been researching this for a coupe of day now without a clear answer. I was wanting to go with a set of Brembo quad pistons such as the one's from the discontinued M2300-X the Focus SVT kit. As I understand it, the Brembo Gran Turismo kits are supposedly the same, but I was wanting to be sure. I have opportunity to source these calipers from 350z/G35's, STi's, Evos, Sentra Spec-V's etc, but I wanted to know which of these cars, if any, will have calipers I can rebuild that will fit on the standard 13" Cobra rotor and Cobra spindles. I'm basically looking for something I can bolt on with no grinding or modifications.