By Stuart Grant with photography by Etienne Fouche

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There’s a painting (or more correctly a print) that hung on my parents’ living room wall for as long as I can remember. Originally painted by Terence Cuneo, it depicts the 1929 Le Mans scene where the d’Erlanger Bentley stops in the pits to replenish his oil sump and the Jack Dunfee car blasts past. A copy of the artwork also sits in the Vintage and Veteran Clubhouse in Johannesburg and it was while chatting about the memories of searching the picture for the Cuneo trademark white mouse as a kid, that Brian Noik of OldCar.Co.Za asked if I’d like to live the picture. With years in the game Noik has an uncanny ability to find the rarest of rare machinery and he quickly made a call to secure the ride. He did mention that the painted pair of Bentleys were 4½-litre units but he’d gone one better, finding a 6½-litre Speed Six replicating the car that won the 24 Hour that year with Woolf Barnato and Henry Birkin at the wheel.

Bentley’s rise to the top of the motorsport pile was as fast as the cars they built. Walter Owen Bentley (known more commonly as W.O.) and his brother Horace Millner started selling French cars from Cricklewood in North London in 1912, but from outset W.O. had aspirations of building his own car – one that would outperform the French cars they offered, which he felt were somewhat mediocre performance-wise. His first step was engineering upgrades for existing vehicles by modifying the crankshaft and replacing the cast-iron pistons with lighter aluminium items – an idea he supposedly got when picking up an ally paperweight. With WWI in full swing the first of these W.O. engine enhancements was applied to power units in the Royal Air Force’s Sopwith Camel and Snipe aircraft, which led to him receiving £8 000 from the Commission for Awards to Inventors – just enough to start up his own car-building business, Bentley Motors Ltd. in August 1919, with the focus on combining luxury with performance being critical.

Unbelievably, five years later Bentley won Le Mans when Captain John F. Duff and Frank Clement drove Duff’s personal Bentley 3-litre Sport to victory at the 1924 event. Once was not enough and Bentley went on to win the gruelling race from 1927 to 1930 with size, strength and reliability being the key factors – fellow race car builder Ettore Bugatti is quoted as referring to the Bentleys as ‘the world’s fastest lorries’. This was not really a fair comment though as W.O.’s designs were technically advanced too, with the 1924 winner the first car to feature four valves per cylinder and twin spark plugs.

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While the race results were impressive the company’s finances were not, but respite came from a group of well-heeled motoring enthusiasts. Made up of Dr. J. Dudley ‘Benjy’ Benjafield, Woolf ‘Babe’ Barnato, Sir Henry ‘Tim’ Birkin, John Duff, Frank Clement, motoring journalist S.C.H. ‘Sammy’ Davis, John Duff, steeplechaser George Duller, Clive Dunfee, Jack Dunfee, Dudley Froy, Baron Andre d’Erlanger, engineer Clive Gallop, aviator Glen Kidston, pearl fishery magnate Bernard Rubin, Bertie Kensington Moir and French racing driver Jean Chassagne, these chaps lived the highlife, partying and driving hard. W.O.’s cars, with all the luxury and performance, were their weapons of choice and the posse soon became known as the Bentley Boys.

In 1925 the books really looked poor and facing closure Barnato, heir to Kimberley diamond magnate Barney Barnato, stepped up to the plate and became the majority shareholder of Bentley.

With coachbuilders fitting bigger and heavier bodies to customers’ road cars Bentley increased the 3-litres chassis dimensions and looked into generating more power. Birkin was convinced the solution was a supercharger but W.O. turned his nose up at this idea, believing that increasing displacement was a more preferable solution than forced induction – especially under the rigours of endurance racing. Both kept up their philosophies with Bentley developing a 4½-litre engine while Birkin, with the blessing from Barnato’s cheque book, roped in Amherst Villiers to engineer a supercharged version known as the Blower Bentley. The story goes that W.O. wouldn’t allow his engine to be modified to incorporate the supercharger, resulting in the supercharger being placed at the end of the four-cylinder’s crankshaft, in front of the radiator, giving the Blower Bentley an easily recognisable appearance but also increasing understeer as the extra weight sat in front of the axles.

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Hindsight would have haunted Birkin though. The Blowers were fast but proved unreliable – two entered the 1930 Le Mans 24 Hours race but neither finished. The W.O. four-pot 4½ units were however just what the doctor ordered, with the Barnato/Bernard Rubin version taking the 1928 Le Mans win and a pair, as mentioned earlier and depicted by Cuneo, came home second and third in 1929 behind a Speed Six.

As the name suggests the Speed Six, introduced in 1926, makes use of a six-cylinder engine – in simplistic terms the 4½ engine with an extra two pistons added. The development started off in 1924 with a 4½-litre straight-six derived from the 3-litre lump. W.O. had fitted the test unit to a chassis and in order to hide the car’s real identity fitted it with a large Freestone and Webb tourer body and registered it as a Sun. Part of his test session included driving the Sun down to watch the 1924 French Grand Prix in Lyon. By coincidence, on the way home he pulled up next to another disguised car and recognising the driver as the Rolls-Royce tester, a dice soon ensued. The cars were inseparable, with the race only ending when the Rolls driver had to stop to pick up his hat that had blown off. This little race played a major role in real races to come.

Bentley was made aware that the Sun had no real performance advantage over the Rolls and had to do something. The solution was true to his theory of no replacement for displacement and he increased the six-cylinder’s bore from 80mm to 100mm, thereby enlarging the capacity of the engine to 6597cc. Again he employed an overhead camshaft, four valves per cylinder and a single-piece cast-iron block/cylinder head, eliminating the need for a head gasket.

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In its most simplistic configuration, with a single Smiths five-jet carburettor, twin ignition magnetos and 4.4:1 compression ratio the 6½-litre delivered 147 horses at 3500rpm. Wearing large, heavy coachwork it was however not an ideal race car but its heart was as good as gold, and so in 1928 Bentley offered up the power unit to a shorter chassis with lighter bodywork and the Speed Six was born. With twin S.U. carbs, a new camshaft profile and 5.3:1 compression ratio the road-going Speed Six upped the game to 180bhp at 3500rpm but the team cars that took part at Le Mans topped the magical 200bhp mark, thanks the addition of another carburettor and 6.1:1 compression figure. This, coupled with a lightweight body that used fabric panel skins (as opposed to metal), created the ultimate performance car that went on to win Le Mans in 1929 and take positions one and two the following year – Barnato teamed up with Glen Kidston to win and Frank Clement secured second, sharing with Richard Watney.

With race-derived details in abundance this beautifully created team car replica brings home the point that the big Bentley is more than just a powerful engine or fast truck. Every aspect of the car shows W.O.’s endurance racing focus, and how the cars were made to be comfortable and easy to drive speedily for long periods, quick to service at pit stops and in the event of a mechanical problem out on track, carry the tools and parts required to get going again. The attention to detail is phenomenal – just look at the quick release flip-top fuel filler cap (opening into the largest tank neck to ensure fast refuelling), the door handle protruding out the top so the pit crew can easily open the door from the outside, a stone guard on both the headlights and petrol tank, knock-on Rudge-Whitworth wire wheels, chicken mesh to hold the exhaust insulation in place, firewall mounted spare spark plugs and best of all is how the leather bonnet-securing belts are folded to make for quick, singlehanded undoing.

Between 1926 and 1930 Bentley made 362 road-going 6½-litre and 182 Speed Six vehicles, and while the Blower Bentley is often the most talked about, the Speed Six is the most successful. W.O. Bentley was an ingenious engineer that meticulously considered every part’s individual function and then manufactured them with such attention to detail that they not only operated reliably under the hardships of sustained spirited driving but were also a work of art. And the Speed Six race cars were the pinnacle of this approach.

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