 This produced 510 crank hp and 510 ft lbs of torque.The difference between the A and B models is the belt drive for the supercharger - the A series uses a single belt, the B series uses a dual-belt system Front-End Accessory Drive (FEAD).Other Roush cars produced in this era were the 2008-only Roush 427R TrakPak, with upgraded suspension components, forged wheels and large APC carbon fiber wing, Roush Drag-Pak Mustangs, and various one-offs for Cooper Tires and certain dealers of Roush products.