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Successful Perversion & Corruption – 4 1/2 Litre Supercharged “Blower” Bentley #HB 3402

Bentley Boy Tim Birkin was described by W.O. Bentley to be “the greatest Briton of his time”, despite the fact that W.O Bentley adhered to a dogma of “there is no substitute for cubic inches” while the latter thought that supercharging, as was the norm for Mercedes Benz and many others was the way to go.

4 1/2 litre S/C Bentley, Brooklands Double Twelve

With W.O. Bentley’s disapproval but with the approval majority Bentley share holder Woolf Boranto, Tim Birkin and Mike Couper formed Birkin & Couper Ltd in Welwyn to supercharge the 55 4 1/2 litre Bentley’s required to meet the regulations to enter a team of three such cars at Le Mans for the 24 hour classic in 1930.

4 1/2 litre S/C Bentley, Brooklands Double Twelve

The whole Birkin & Couper enterprise including the three entries at Le Mans was funded by successful horse race breeder and owner Dorothy Paget. W.O. Bentley said of the operation “They would lack in their preparation all the experience we had built up in (our own) racing department over 10 years. I feared the worst and looked forward to their first appearance with anxiety…”.

4 1/2 litre S/C Bentley, Brooklands Double Twelve

W.O. Bentley’s anxiety proved to be correct as the “Blower” Bentley’s proved to be unreliable with a best 2nd place overall and first in class being recorded in the 1929 Tourist Trophy in Ulster with Birkin at the wheel and W.O. Bentley in the passenger seat, the result of a bet which W.O. had accepted.

4 1/2 litre S/C Bentley, Brooklands Double Twelve

The team of three 4 1/2 litre Blower Bentley’s all retired at Le Mans in 1930, the win being secured by a normally aspirated 6 1/2 litre Bentley, as it had been, in 1929 which vindicated W.O. Bentley’s assertion regarding cubic inches and led W.O. to claim “The supercharged 4½ never won a race, suffered a never-ending series of mechanical failures, brought the marque Bentley disrepute and incidentally cost Dorothy Paget a large sum before she decided to withdraw her support in October 1930…”.

4 1/2 litre S/C Bentley, Brooklands Double Twelve

However W.O. spoke too soon because in 1929 “Tiger” Tim Birkin had also persuaded supercharging experts Amehust Villers, Baranto, Paget and Captain Clive Gallop to develop a special track racing car for competition at Brooklands. Chassis #HB 3402 was fitted with a methanol burning four cylinder engine, #SM 3901, was given a special fabric skin body, originally painted blue in 1929.

4 1/2 litre S/C Bentley, Brooklands Double Twelve

The cars one outing at Brooklands 1929 included several mishaps, a loose fuel tank, an oil leak, exhaust pipe disintegration and a subsequent fire. For 1930 this 1 1/2 seater was producing 240 hp, 65 more than a standard Blower, that burnt 1 imperial gallon of fuel every 74 seconds !

4 1/2 litre S/C Bentley, Brooklands Double Twelve

With a new, fire proof, body designed by Reid A. Railton and built by A.P. Compton & Co of Merton, Tim drove #HB 3402 to victory in the Kent Long Handicap run over just four laps of 2.75 mile circuit. Tim had little good to say about the Brooklands Outer Circuit, thanks to the poor condition of the track which frequently saw cars going airborne with all four wheels well clear of the ground.

4 1/2 litre S/C Bentley, Brooklands Double Twelve

Birkin won two further races driving HB 3402 at Brooklands in 1931 and 1932 and held the outright track record on several occasions, leaving it at 137.58 mph in the 1932 August Brooklands Meeting winning 100 Sovereigns as the car won it’s third race a 3 lapper. By now the car had been painted red as seen here. By comparison pole at Indy that year was won by Lou Moore in the Boyle Valve Special Miller at 117.363 mph.

4 1/2 litre S/C Bentley, Brooklands Double Twelve

W.O. Bentley said of forced induction “to supercharge a Bentley engine was to pervert its design and corrupt its performance”, a comment that was not reflected in # HB 3402’s price earlier this year when the 1 1/2 seater with a blower set another record at Bonham’s fetching UK £ £5,042,000 to become the most expensive Bentley ever bought at auction.

Thanks for joining me on this “Successful Perversion & Corruption” edition of “Gettin’ a li’l psycho on tyres I hope you will join me again tomorrow. Don’t forget to come back now !

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