2016 BMW ALPINA B6 Gran Coupe is the newer version with some differences, such as the horsepower and fuel economy.. And finally, the 2016 BMW ALPINA B6 Gran Coupe has a more powerful engine and gets 1 mpg less than the 2015 BMW ALPINA B6 Gran Coupe. Among similarities are the body structure, market segment, starting price, ground shadow size, height, and maximum occupancy.