Origins
Bentley Motors developed the 4½ Litre as a replacement for the Bentley 3 Litre, increasing engine displacement to 4.4 litres (270 cubic inches). The 24 Hours of Le Mans, established only a few years earlier, quickly became a key competition for automotive manufacturers seeking to elevate their reputation. The inaugural race was held in 1923, attracting primarily French drivers, though Canadian John Duff won the 1924 competition in a Bentley 3 Litre.
Breakthrough
The 4½ Litre was conceived within a context of renewed investment in Bentley’s racing program, funded by a group of wealthy British enthusiasts nicknamed the “Bentley Boys.” These drivers and mechanics drove Bentley automobiles to victory in several races between 1927 and 1931, including four consecutive wins at the 24 Hours of Le Mans. The first 4½ Litre was raced as a prototype at the 1927 24 Hours of Le Mans, crashing before finishing, but demonstrating enough potential for Bentley to begin production that same year.
Peak Seasons
In 1928, three 4½ Litres finished second, third, and fourth at Le Mans, behind a Bentley Speed Six. The naturally aspirated 4½ Litre was noted for its reliability. Sir Henry “Tim” Birkin, described as “the greatest British driver of his day,” challenged the prevailing belief that increasing displacement was always preferable to forced induction. He began development of a supercharged version, the Blower Bentley, with the support of Bentley chairman Woolf Barnato and financier Dorothy Paget.
Defining Incidents
In 1930, Birkin finished second in the French Grand Prix at the Circuit de Pau driving a Blower Bentley, behind a Bugatti Type 35. Ettore Bugatti, annoyed by the Bentley’s performance, reportedly called the 4½ Litre the “fastest lorry in the world.” Despite the Blower’s reputation for unreliability, Mildred Bruce achieved a 24-hour distance record at Montlhéry in one, averaging 89.4 mph (143.9 km/h). In 1932, Birkin won the Daily Herald Trophy at Brooklands driving his red Blower "Monoposto," clocking 137.96 mph (222.03 km/h).
End of Production
In November 1931, after producing 720 copies of the 4½ Litre—655 naturally aspirated and 55 supercharged—Bentley was forced to sell his company to Rolls-Royce for £125,175, a consequence of the economic recession following the Wall Street crash of 1929.
Current Status
As of 2013, Bentley 4½ Litre automobiles from this period sold for around €1,000,000. Blowers can fetch more than €7 million and are highly sought after by collectors despite their lack of major race wins. For some, the 4½ Litre represents the pinnacle of automotive design, comparable to the Spitfire in aviation.
Popular Culture
James Bond drives a 1930 Blower Bentley in Ian Fleming's first three novels – Casino Royale, Live and Let Die, and Moonraker. Bond drives a battleship grey Convertible Coupé, equipped with French Marchal headlamps.