Bentley fires up first new Blower engine on a Spitfire test rig
09 September 2020
The first new 4.5-liter Blower engine to built at the Bentley factory for 90 years is being bench tested on a rig that previously held Spitfire and Hurricane engines.
The original testbeds had long gone, but Bentley did still have a unit for the Merlin V-12 aero engine that was instrumental in winning the Battle of Britain. With the Blower motor held in place it can be rigged up to a modern computer-controlled dynamometer to be put through its paces.
The first test cycle lasts 20 hours to run in the engine, after which it will be fitted to the prototype Blower Bentley Continuation for a full road-test program. Only after this “Car Zero” has completed over 20,000 miles on road and track will Bentley begin production of the 12 pre-sold, $2 million customer cars.
The 4.5-liter engine was designed by W.O. Bentley himself, but “Bentley Boy” Tim Birkin craved more power than the 132 hp W.O. was offering. Birkin got financial backing from wealthy horse and motor racing enthusiast Dorothy Paget and turned to Clive Gallop and Amherst Villiers to build a supercharger. The Roots-type blower was mounted ahead of the engine and radiator and driven directly off the crankshaft. With reinforced internals, including connecting-rods and crank the Blower engine added just over 100 hp.
The Blower Bentley was very quick, but never won a race in 12 outings as it kept breaking down. Bentley will, no doubt, be hoping the extensive testing of the ‘new’ version will make it rather more reliable.