Overview Manufacturer Porsche AG Production 1963–present Assembly Germany: Baden-Württemberg, Stuttgart Designer Ferdinand Butzi Porsche (original design) Body and chassis Body style 2-door coupé 2-door convertible 2-door targa top 2-door speedster Layout Rear-engine, rear-wheel drive / four-wheel drive The 911 has been modified by private teams and by the factory itself for racing, rallying, and other forms of automotive competition. It is among the most successful competition cars. In the mid-1970s, the naturally aspirated 911 Carrera RSR won major world championship sports car races, such as Targa Florio and 24 Hours of Daytona, even against prototypes. The 911-derived 935 turbo also won the 24 Hours of Le Mans in 1979 and Porsche won World Championship for Makes titles in 1976, 1977, 1978 and 1979 with 911-derived models. Note this is a Porsche 911 track day experience Compared to the 997, the 991 is slightly larger, with the wheelbase increased by 100 mm (3.9 in) to 2,450 mm (96.5 in), and the overall length up by 70 mm (2.8 in) to 4,490 mm (176.8 in).[2] A new transaxle was developed so that the rear wheels could be moved 76 mm (3 in) backward in relation to the position of the engine, which significantly improves the weight distribution and cornering performance of the car.[3][4]