Design :
Designed by Ernest Henry in Suresnes, with input from Louis Coatalen and the Sunbeam Experimental Department Wolverhampton. Jean Chassagne was liaising and also in charge of testing. Before the Great War Ernest Henry was a part of the successful and innovative ‘Charlatans’ who designed the first ever dohc four valve Grand Prix engines for the 1912 Peugeot ; the 1922 Sunbeam design follows similar principles. The aluminum body was the latest in streamlining and is typical of the Post Great War Henry design with the spare wheel carried longitudinally in the tail and braced by the large fuel tank. Each of the three team cars was designed around its intended driver integrating each driver’s requirements and preferences. The asymmetrically inclined valves (inlet 20 degrees and outlet 40 degrees from vertical) were a significant departure for Henry and may be attributable to Sunbeam and Coatalen whose interest in desaxé configuration dated to 1911. Another unusual detail was the engine mounted directly on the chassis frame. Following tests in Brooklands and Isle of Man prior to the Grand Prix , modifications were instigated to the tail support bracket. Different carburetor configurations and different tyre types were tried , axle ratios experimented with, aero screens and mudguards were installed or removed as required.