In October 1919, Bentley Motors’ first-ever engine, the 3 Litre, burst into life in New Street Mews, near Baker Street, London. Soon after, EXP-1, as both the prototype engine and chassis were codenamed, was previewed at the Olympia motor show in London. Careful testing prior to the start of production caused delay, and the production began finally in 1921, in a new factory in Cricklewood, north London. The first 3 Litre production car, the first car ever named after its cylinder capacity, was delivered in September that year. For customers Bentley delivered only a rolling chassis. The bodyworks for customers’ cars were built by coachbuilders.
Bentley’s 4-cylinder in-line engine with the capacity of 2,996cc featured many technical innovations, such as aluminium pistons, an overhead camshaft and 4 valves per cylinder. Iron engine block and cylinder head were cast as a single unit. The engine had a long stroke of 149mm, which provided lot of low-end torque. The engine produced around 70 horsepower. The car could reach top speed of 80 mph. In addition to the basic version TT models and Speed models were offered. The Super Sports could exceed 100 mph. The engine’s power was transmitted through a four-speed gearbox. The first cars only had rear wheel brakes. The front wheel brakes were introduced in 1923. The suspension was semi-elliptic springs on front and rear axles.
Walter Owen Bentley reckoned racing was the best way to promote the new company and the new car. However, the big and heavy Bentley 3 Litre didn’t suit well in Grand Prix racing. Instead it was perfect for endurance racing due to its strong and reliable engine. Bentley’s first victory was at Brooklands won by works driver Frank Clement. In the 1922 Tourist Trophy Bentley 3 Litres finished second, fourth and fifth driven by Clement, W. O. Bentley and Hawkes. In the Indianapolis 500 Hawkes drove the Bentley 3 Litre to 13th place.
John Duff and Frank Clement took part in the Le Mans 24 Hour race in 1923 and 1924 as a private team racing with their own car. They came fourth in 1923, delayed by a punctured petrol tank, but in 1924 they took the first Le Mans win for Bentley. Next year Bentley participated Le Mans with a factory team. In 1927 Sammy Davis and Dudley Benjafield drove their 3 Litre car to an epic victory at Le Mans. After all three Bentleys were involved in an accident at White House corner at around 9pm, only one car was able to continue. Sammy Davis managed to extricate his 3 Litre, known as “Old No.7”, and limped back to the pits with a buckled wheel, a smashed headlamp and damage to the offside wing. Worse, though, was the pushed-back front axle, upsetting the brake compensation.
Davis and Benjafield drove on through the night, relying on a policeman’s torch strapped to the windscreen pillar. As noon came round the second-placed Bentley was gaining on the leading car, a French Aries. Noticing a knock in the Aries’ engine, the Bentley pit hung out the “Faster” sign. Rising to the challenge, “Old No.7”, Davis and Benjafield pulled out the stops, to win the race at an average of 61.35 mph. The victory was celebrated afterwards at the Savoy hotel, and the dinner was attended by “Old No.7” herself.
Racing success boosted Bentley sales. Between years 1921 and 1929, Bentley manufactured 1622 cars with the 3-litre engine.