Two Coupes with some similarities, but otherwise different in most aspects such as the modifications, starting price, model year, horsepower, fuel economy, and height. First of all, the 2014 Mercedes-Benz C-Class Coupe C63 AMG is priced $67,650 lower compared to the base MSRP of the 2016 Porsche 911 Coupe GT3, which is newer by two model years. Also, the 2016 911 Coupe GT3 has a more powerful engine than the 2014 C-Class Coupe C63 AMG, but it gets 2 more miles on a gallon of fuel. In addition, the C-Class Coupe C63 AMG has a slightly taller body than the 911 Coupe GT3. Among similarities are the body structure, market segment, ground shadow size, and maximum occupancy.