Speed is Dieselpunk

Railton Special, the mount of John Cobb. Two land speed records, also set at the Bonneville Salt Flats: 353.30mph (568.58 km/h) on September 15, 1938, and 369.70 mph (594.97 km/h) on August 23, 1939. This is a post-war photograph of the Special, rebuilt and rebadged. On September 16, 1947 John Cobb averaged 394.19 mph (634.39 km/h) over the measured mile in both directions to take his third land speed

(via Dieselpunk Encyclopedia)