The only significant upgrade in the Roadster's production came in September 1948 for the 1949 models, when the 2088 cc Vanguard engine, transmission, and rear axle were fitted. With the larger engine the four-speed gearbox was replaced with a three-speed unit, even though it now had synchromesh on bottom gear. Apart from minor modifications to the mounting points, the chassis, suspension and steering were unaltered. This later version of the Roadster was given the model designation 20TR.
