The burliest Mustang loses some weight and gains 10 hp and an optional track-focused package for 2011. The Blue Oval is leaving no Stang untweaked for 2011, now announcing significant updates to the Shelby GT500 to go along with the already revealed 5.0-liter Mustang GT and base 3.7-liter V-6 cars . The most important alteration to the Shelby is a switch in engine-block material, tossing the old cast-iron block for a version of the all-aluminum lower end that was originally developed for the Ford

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2011 Ford Mustang Shelby GT500 – Official Photos and Info