I don't think I ever really get into the history of why Bentley developed a Blower in the first place. Not important to the story. Besides, the missing Blower SM 3912 was not fitted with a racing body. It had a two-seater Phillips drop head coupe body fitted. But, besides the point. Even in the '30s the consumer buyers of cars wanted to have as close to the racing version of a car as possible.
So, with that in mind, I've got a link to a bit of history on the characters who started the whole supercharged Bentley thing. Lots of it do with a Tim Birkin, who loved the Blown cars and used one to raise the Brooklands lap record to nearly 138MPH in 1932! Egads it must have been a ride going near to the top speed of a Porsche 944 in fancy tractor.
Check out the story at www.bentleygreenpower.com.