Two Convertibles with some similarities, but otherwise different in most aspects such as the starting price, fuel economy, horsepower, ground shadow size, and height. First of all, the 2017 Porsche 911 Convertible is priced $44,040 lower compared to the base MSRP of the 2017 Maserati GranTurismo Convertible. Also, the 2017 911 Convertible has a more powerful engine than the 2017 GranTurismo Convertible, but it gets 7 more miles on a gallon of fuel. And finally, the GranTurismo Convertible is both slightly larger and taller than the 911 Convertible. Among similarities are the body structure, market segment, and maximum occupancy.