The post-war period was difficult for the motor industry as military contracts were cancelled and military vehicles no longer required for service were sold onto the market at low prices. Guy returned to the civilian market, deciding to make luxury cars with a design by R. H. Rose, also from Sunbeam. They produced the Guy 8-cylinder car, powered by the first British V8 engine and featuring horizontal side valves. Around 25 of these were made and it was joined by a smaller model in 1922 with the 2465 cc four-cylinder 16.9 hp. A cheaper model followed in 1924 with the 1954 cc 13/36 with an engine from Coventry Climax. About 110 of the 4-cylinder models are thought to have been made. Production also continued on vehicles based on the 30cwt chassis such as the Guy charabanc and their major success the 30 seater bus.