Bentley has updated its Continental GT for the upcoming 2013 model year, showing off the auto makers new focus on efficient power and refined luxury. The 2013 Bentley Continental GT V8 ditches the W12 engine of the last model for a twin-turbocharged V8 that pushes comparable power. This 500 hp system will race to 60 mph in under five seconds, on its way to a top speed of nearly 180 mph. With four less cylinders than 2011