Answer by
Sara89 (367)
According to the manufacturer's information, the new 2011 Shelby 500 GT has 550 horsepower. That's about 10 more horses than the 2010 model. The main difference between the two is the 2011 has switched to the lighter aluminum 5.4L engine - the 2010 had a heavier cast-iron 5.4l. The weight difference of about 100lbs provides the extra horsepower. vroom!