In the 60s, motor racing engineers started to take aerodynamics seriously. They discovered that if they reduce the slope of the back of a car to 20 degrees or less, the air flow will follows the roof line smoothly and dramatically reduce the drag. They termed this design as "Fastback". As a result, many racing cars, such as the Porche 935 / 78 "Moby Dick" shown here, added an exaggerately long tail and lower the back.