Bentleys by Bentley: Designed by the Man Himself

In our ongoing series on how to go bankrupt making racing cars (or really, any cars), we are moved to present the Bentley saga. Engineer William Owen Bentley was not alone in being convinced that racing cars was the best way to sell them.  As it turned out, racing was a good way to publicize Bentleys because they won a lot, but in order to win Le Mans 5 times between 1924 and 1930, Bentley had to sink more cash into building the cars than he could get out of selling them.  The first Bentleys appeared in 1921, and while it took awhile for W.O. to adopy four-wheel brakes, he adopted overhead cam, multi-valve engines from the start.  This 1926 Super Sport was guaranteed to hit 100, and featured a single-overhead cam 3.0 liter inline four with four valves per cylinder.  A sister car would win the Le Mans 24 Hours the next year...

This Surbiton-bodied boat-tailed roadster was one of only a dozen and a half Super Sports built, out of over sixteen hundred Three Liters in all. The radiator was specially ordered in a profile that tapers inward towards the base, an attractive and rare option. 

Generous use of wood trim, inside and out, relates to the nautical theme of the body design, which was named "skiff" by the builders..

Bentley chose long-distance races like Le Mans because they could make best use of his car's strong points: durability and speed on long straights. His team, later nicknamed the Bentley Boys, avoided races on tight, twisty courses. Bentleys tended to have weight to match their stoutness. The Super Sport, on the short 9 foot wheelbase, is the lightweight of our featured cars, at just over 3,400 pounds.  Bentley introduced a 6.5 liter inline six in 1926, and the next year, shaved two cylinders off the new engine design to produce the 4.5 Liter.

A 4.5 Liter roadster in the hands of Woolf Barnato, one of Bentley's funders, and Bernard Rubin won Le Mans in 1928.  Attractive touring versions of the 4.5 were produced on the long wheelbase variant, like the 1929 tourer by Thrupp and Maberly above.  Meanwhile, the pressure to keep winning prompted a debate about Bentley's next racer.  W.O. preferred to make a racing version of the big 6.5 liter six, while drivers Henry Birkin and W. Barnato liked the idea of superchaging the 4.5 liter four. The firm tried both approaches; a 4.5 liter supercharged "Blower Bentley" in touring guise is shown below...

…and a short-chassis Blower Bentley from 1930 charges up a hill here.  But as it turned out, despite later mythologizing of the Blower Bentley by the likes of Ian Fleming (007 drove one in the early stories), the Blower Bentley lacked the reliability of the unblown 4.5, and 3.0, and the newer, smoother 6.5.  Bentley built 55 of the Blower model; a minimum of 50 were required to qualify at Le Mans.  But none of the supercharged cars ever won there.

W.O. Bentley's engineering instincts were proven right when his Speed Sixes won Le Mans in 1929 and 1930. A 1930 version of the Speed Six is shown with expansive (and expensive) touring body below.  The big six shared engine architecture with the other Bentleys, including 4 valves per cylinder, and an iron block cast in one piece with the head to avoid head gaskets...

Note that this car has a fabric-bodied cabin somewhat like the Weymann bodies on some Stutzes and Duesenbergs, while the fenders and bonnet are in metal.  Weight was over two tons...

Because of his expenditures on racing cars, and despite the paticipation of wealthy benefactors like Barnato and Birkin, Bentley's enterprise was already.skating on thin ice when the Great Depression arrived.  He'd wanted to introduce a bigger luxury car aimed at Rolls Royce and Daimler, and at the 1930 Olympia Motor Show he introduced the 8 Liter model to an enthusiastic (but small) public. The 8 liter engine, an inline six, shared its mechanical details with the 6.5, and made 250 horses at a leisurely 3.500 rpm.

The example shown here was bodied by Corsica* in 1932, the year after W.O. Bentley's car-making operation went bankrupt.  Only a hundred examples the 8 Liter would be built by the end. This specimen's owner decided to shorten the wheelbase to a still-whopping 12 feet, and rebody a saloon in the sports tourer style.  It was one of two 8 Liters bodied by Corsica, and also one of the few with performance modifications by tuner L.C. McKenzie... 

How fast was it?  Well, in 1950, a Bentley 8 Liter like this one, with the McKenzie tuning, set an official record for the flying mile at 134.75 mph.  For a brief while, then, a 20 year-old car was officially the fastest sports car in the world.  

There were, of course, other Bentleys built after the Rolls Royce takeover, after that summer of 1931 when W.O. Bentley's dream came to an end.  But they were more sedate, and without the eccentric mechanical details Bentley the man prized. Many racing seasons later, W.O. Bentley's engine designs would show up again at Le Mans, but they would be in cars made by Lagonda* and then Aston Martin*, not in the smooth, silent Bentleys made by Rolls Royce.

*Footnote:  For a close look at another car bodied by the Corsica Body Works, see "Forgotten Classic: Adrian Squire's Namesake Car", in our Archives for April 23, 2018.  The Lagonda history, including W.O. Bentley's involvement, is summarized in "Forgotten Classic: Lagonda—A River Ran Through It", posted September 10, 2020.  And the story of the Bentley-designed Lagonda engine in Aston Martins is reviewed in "Rescued from Obscurity:  Aston Martin in the Fifties and Sixties", posted May 11, 2020.

Errata:  A little while after this piece was first posted, we accidentally wiped out half the first paragraph when attempting to correct something else.  Apologies to anyone attempting to make sense of our essay.  It's fixed now, we think.

Photo Credits:
Top (1926 Bentley Super Sport) :  the author

2nd thru 5th ('26 Super Sport):  Ian Avery-DeWitt

6th (4.5 Liter Thrupp & Maberly);  Wikimedia:

7th (4.5 Liter Supercharged, monochrome):  simeonemuseum.org

8th (1930 4.5 Liter): Wikimedia
9th: (6.5 Liter Speed Six):  Paul Anderson

10th & 11th (Speed Six):  Ian Avery-DeWitt

12th thru bottom  (Bentley 8 Liter):  Ian Avery-DeWitt