Following the acquisition of Bentley Motors in November of 1931, Rolls-Royce had the task of transforming their 20/25HP into a distinct sports car that W.O. Bentley would approve of.
As a result the Bentley received a cross-flow cylinder head and signature SU Carburetors that made it a sporting alternative to Rolls-Royce 20/25HP.
Ernest Walter Hives worked hard with his team to make the best sports car possible and upon testing a prototype, W.O. Bentley said “taking all things into consideration I would rather own this Bentley car than any car produced under that name.”
The sales department first released the car at the 1933 Olympia Motor Show and described it as the Silent Sports Car with a top speed of 95 mph.
Both the 20/25HP and 3½ Litre were built at the Rolls-Royce factory in Derby England as a rolling chassis, complete with scuttle and radiator to be bodied by a coach builder of the customer’s choice.
Many were completed as Park Ward Sports Saloons as Rolls-Royce had partial ownership of Park Ward during production which led to almost half the production going to them. Many 3½ Litres were fitted with coachwork that was common on the Rolls-Royce Phantom II from designers like Barker, Hooper, H.J. Mulliner, Gurney Nutting, Thrupp & Maberly and Vanden Plas.
The 3.675-liter engine used a higher compression ratio than that of the Rolls and when combined with two SU carburetors could raise the top speed to 145 kph. It’s relative smooth running operation befit the cars Silent Sportscar nickname.
The model was first announced in the 1933 but customer deliveries began in 1934 with Rolls-Royce’s technical support. Eddie Hall drove a sporting example in the 1934 Tourist Trophy right before the model was offered to the public.
In 1937 the model was replaced outright by the 4½ Litre.
| type | Series Production Car |
| production years | 1934 – 1936 |
| released at | 1933 Olympia Motor Show |
| built at | England |
| engineers | Ernest Walter Hives |
| production | 1191 |
| succeccesor | 1929 Bentley 4½ Litre |
| engine | Inline-6 |
| position | Front, Longituinal |
| aspiration | Natural |
| block material | Cast Iron |
| fuel feed | Twin SU Carburetors |
| displacement | 3675 cc / 224.26 in³ |
| bore | 82.5 mm / 3.25 in |
| stroke | 114.3 mm / 4.50 in |
| power | 82.0 kw / 110 bhp @ 4500 rpm |
| specific output | 29.93 bhp per litre |
| body / frame | Body over Nickel-Steel Chassis |
| driven wheels | RWD |
| wheel type | Spoked Wire |
| front brakes | Drums w/Servo Assist |
| rear brakes | Drums w/Servo Assist |
| steering | Worm and Nut |
| f suspension | Solid Axle w/Semi-Elliptic Leaf Springs, Hydraulic Dampers |
| r suspension | Live Axle w/Semi-Elliptic Leaf Springs, Ride Control Hydraulic Dampers |
| transmission | 4-Speed Manual |
| top speed | ~152.85 kph / 95 mph |
| fuel capacity | 68.13 litres or 18 ga |
