Sunbeam 90 Mk III

 From 1954 to 1957 the car continued, but without the Talbot name and was marketed as the Sunbeam MkIII and badged on the radiator shell as Sunbeam Supreme. The drophead coupé was not made after 1955.

There were some minor styling changes to the front with enlarged air intakes on each side of the radiator shell and three small portholes just below each side of the bonnet near to the windscreen. Duo-tone paint schemes were also available. Engine power was increased to 80 bhp (60 kW)and overdrive became an option.

A Mk III tested by The Motor magazine in 1955 had a top speed of 93.6 mph (150.6 km/h) and could accelerate from 0-60 mph (97 km/h) in 17.4 seconds. A fuel consumption of 22.1 miles per imperial gallon (12.8 L/100 km; 18.4 mpg_-US) was recorded. The test car cost £1191 including taxes.

The main Rootes Group dealers in Leicester, Castles of Leicester, offered a conversion that moved the gearchange to the transmission tunnel, modified the cylinder head, fitted a bonnet air scoop and changed the way the boot lid opened. These models were not connected with the Sunbeam factory but are sometimes referred to as the Mk IIIS. Some 30-40 cars were modified. The revised gearchange was also offered as an after market accessory and was suitable for fitting to earlier models also.

Approximately 2250 were made.