|Not the same car the video was shot from, but a Blower Bentley at LeMans: close enough|
Here's a fun video invoking the days when tires were skinny and drivers were fat. The Bentley 4.5 liter lacked synchromesh on all gears:
I dimly recalled that the most iconic Bentley of them all didn't win LeMans--the race it was built for. (It has often seemed to me that the British fascination with LeMans in the '30's, '40's, and '50's stemmed from Bentley's wins there in 1924, 1927, 1928, 1929, and 1930. And also because the U.K. couldn't field a competitive Formula 1 car in those decades.) So off I went to Wikipedia for the story of the Blower Bentley. Here's the link for those who want more:
It turns out that W.O. Bentley didn't approve of supercharging, which, by 1930, was commonly used by Alfa Romeo, Bugatti, and Mercedes-Benz for racing. W.O. wanted torque, which required cubic inches. He believed in big engines in big cars: 3, 4.5, and 6.5 liter fours and sixes. The standard 4.5 liter weighed 3600 lbs. This was the antithesis of the Alfas and Bugattis of the day and led to a notable passive-aggressive put-down by Ettore Bugatti: "Monsieur Bentley builds excellent trucks." (Bentley was not opposed to high-tech, though: the 4.5 liter had 4 valves per cylinder driven by an overhead cam.)
One of the Bentley Boys, Tim Birkin, wanted more power for LeMans. Another, Woolf Barnato, had bought a considerable stake in Bentley, and was a Director. He agreed with Birkin, so W.O. couldn't prevent the project from going forward. They hired Villiers to design and build 5 Roots-type blower editions of the 4.5 for racing generally and LeMans in particular. But W.O. didn't have to cooperate, and he didn't. He refused to redesign the 4.5 to use a gear train to drive the supercharger. This resulted in the Blower Bentley's iconic look: the supercharger was visible without raising the hood, hung off the front of the engine between the frame rails.