The Bentley S1 was a luxury car produced by Bentley Motors Limited from 1955 through 1959. It marked Bentley parent, Rolls-Royce, reducing the differences between their Bentley and Roll-Royce models, with the S1 differing only in its radiator design and badging from the Rolls-Royce Silver Cloud I.
The models shared the 4.9 L (4887 cc/298 inÂ³) straight-6 engine, with this being the last vehicle to use this engine. The bore was 95.25 mm (3.7 in) and the stroke was 114.3 mm (4.5 in). Twin SU carburetors were fitted, with upgraded models from 1957. A 4-speed automatic transmission was standard, with a 4-speed manual available as an option. Two wheelbases were produced: 123 in (3124 mm) and, from 1957, 127 in (3226 mm).
A somewhat sportier coachbuilt-only S1 Continental was introduced six months later.
S1: 3072 (145 with coachbuilt bodies)