Clive Gallop

Clive Gallop joined the Royal Flying Corps, flying aeroplanes over the Western Front. He commanded a number of flights, including No. 56 Squadron.^[4]

London racing driver, motor vehicle dealer and engineer W. O. Bentley had suggested aluminium pistons to his car supplier Doriot, Flandrin & Parant and had them installed in those cars he imported. Following commissioning on the outbreak of war as an engineer by the Royal Naval Air Service Bentley was sent to Gwynnes pumps workshops in Chiswick which were making French Clerget engines under license. Part of Bentley's duties was to liaise between the squadrons in the field in France and the factory's engineering staff which is how he came to meet Gallop.^[5] Clerget was very unwilling to act on Bentley's more important suggestions so the Royal Navy sent Bentley to Humber Limited in Coventry.

At Humber, Bentley was given a team to design his own aero-engine. The resulting engine, fundamentally different from the Clerget though—for ease of production—alike in the design of the cam mechanism, was running in prototype by early summer 1916. This was the BR1, Bentley Rotary 1, with the bigger BR2 followed in early 1918. Gallop helped Bentley bring both into service with the Royal Flying Corps.^[5]

At the end of hostilities and leaving his commission with the Royal Flying Squadron, Gallop joined the Royal Aero Club.^[2]

In 1919, a group was formed in Cricklewood by W O Bentley, a motor vehicles engine designer, pioneer of aluminum pistons who had turned in wartime to aero engines, to build his own cars. With a group including Frederick Tasker Burgess, formerly of Humber, and Harry Varley, formerly of Vauxhall, he set about designing a high quality sporting tourer copying a Humber chassis brought there for the purpose.^[6]

Gallop joined the team as an engine designer^[7] developing the 3,000 cubic centimetres (180 cu in) straight-4 engine. Although large for its day compared to similar engines from Bugatti, it was its technical innovations that were most noticed.^{[citation needed]} One of the first production engines with 4 valves per cylinder,^{[citation needed]} these were driven by an overhead camshaft. It was also among the first with two spark plugs per cylinder,^{[citation needed]} pent-roof combustion chambers,^{[citation needed]} and twin carburetors.^{[citation needed]} It was extremely undersquare, optimized for low-end torque, with a bore of 80 millimetres (3.1 in) and a stroke of 149 millimetres (5.9 in). To increase durability, the iron engine block and cylinder head were cast as a single unit.^{[citation needed]}

Power output was roughly 70 brake horsepower (52 kW), allowing the final Bentley 3 Litre car via a four-speed gearbox to reach 80 miles per hour (130 km/h). The Speed Model could reach 90 miles per hour (140 km/h), while the Super Sports passed 100 miles per hour (160 km/h).^{[citation needed]}

From 1921, Gallop joined "Count" Louis Zborowski at his Higham Park estate. As well as acting as his co-driver in numerous races, and as driver of the team's second Aston Martin in others (i.e.: 1922 French Grand Prix), he also helped Zborowski design and build four of his own racing cars in the estate's stables.

The first car was powered by a 23,093 cc six-cylinder Maybach aero engine and called "Chitty Bang Bang".^[8] A second "Chitty Bang Bang" was powered by 18,882 Benz aero engine. A third car was based on a Mercedes 28/95, but fitted with a 14,778 cc 6-cylinder Mercedes aero engine and was referred to as The White Mercedes. These cars achieved some success at Brooklands.

Another car, also built at Higham Park with a huge 27-litre aero engine, was called the "Higham Special" – later known as "Babs"- and was used in J.G. Parry-Thomas's fatal attempt for the land speed record at Pendine Sands in 1927.

In January 1922 Zborowski, his wife Vi, Gallop and Pixi Marix together with a couple of mechanics took Chitty Bang Bang and the White Mercedes across the Mediterranean for a drive into the Sahara Desert, in the tracks of Citroen's kegresse expedition.

In 1923, Zborowski joined with American engineer Harry Arminius Miller, driving the single-seat "American Miller 122" at that year's Italian Grand Prix. Zborowski died aged 29 the following year whilst racing for Mercedes-Benz in the same race, after hitting a tree.

At the end of his partnership with Zborowski in 1924, Gallop as a friend of Woolf Barnato rejoined Bentley Motors in 1925 after his friend bought into the business. This led to him both supporting the racing efforts of the "Bentley Boys", as well as developing the engine for the Bentley 4½ Litre.