SMS 620 Camaro features optional Torvec Isotorque Differential... The SMS 620 Camaro accelerates from 0 to 60 in under 4.3 seconds, while the SMS 620X Camaro manages the same in closer to 4.0. In addition to engine output, handling, road holding and braking improvements, the 620X will feature options such as Magneto-Rheological Semi-Active Dampers and Torvec Isotorque Differential and 21" rear wheels. Both will offer new SMS 16" 8-piston front and 14" 6-piston rear brakes deliver impressive stopping power to match rail like cornering and jaw-dropping acceleration. http://blogs.gmhightechperformance.com/6609332/gm-news/sms-2010-chevy-camaro/index.html http://www.egmcartech.com/2010/01/08/2010-sms-camaro-620-620x-first-details-and-photos-of-smss-camaro-modifications/