The GT Track Package and Brembo Brake Package is featured on this page of the 2014 Mustang sales brochure. The text reads Race Ready The GT Track Package1 ups your odds in an instant. TORSEN helical gear differential with 3.73:1 gear ratio. Upgraded radiator. Engine oil cooler. It also includes the Brembo Brake Package with its 14" vented front rotors, unique suspension tuning, 19" wheels with sticky summer - only performance tires and more. For hard corners and other gutsy moves: RECARO Sport seats. Now it's track time.