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Horace Millner Bentley

Over the years many people have tried to improve on W.O. Bentley’s famous automobile platforms. From Woolf Barnato’s Super Sports to the ‘Blower’ Bentley. Each iteration of Bentley has its advantage, but there is one standout model which is a jack of all trades, the Bentley Short Chassis developed by H. M. Bentley.

We can all learn a lot from history, and Bentleys are no different. W.O. Bentley’s brother, H.M. Bentley, used to run a workshop after the factory closed in 1932. H.M. would purchase older Bentleys which had fallen on hard times. He would give them a new lease of life by sprucing up the engine, re-body them and sometimes shorten the chassis to make them sportier, before selling them for a profit. 

Vintage Bentley have taken inspiration from H. M.’s creation and have built several Short Chassis 4 ½ Litre ‘H.M. Bentleys’. The Short Chassis can be described as the best Bentley for four-seater rallying. Pairing a stunning sporting appearance with the benefits of a shorter, more nimble car. The journey starts with an original 4½ Litre Bentley. The car is completely dismantled and the first job on the agenda is to shorten the chassis frame to 9’ 6” from the original 10’ 10” wheelbase. The engine receives a plethora of upgrades and a fettling to bump the power figures up to a respectable 200bhp. To complete the Short Chassis, the car receives every rally modification you could desire to help the car stop as quickly as it accelerates and run as reliably as possible. 

The shortened chassis allows the car to retain its four-seater coachwork, so it is as practical as before but with the added stability and handling which goes hand in hand with a shorter wheelbase. This 9’ 6” shortened wheelbase is a real game-changer for rallying in tight environments with hairpins and switchbacks, just like on the Flying Scotsman. The chassis is shortened behind the driver’s seat, allowing the driver and front passenger in the vehicle to maintain the usual comfort of a standard 4½ Litre Bentley. H.M.’s original creation featured a vertical cut along the chassis, allowing it to be slipped forward into the front chassis rails. This feature added extra structural rigidity and allowed the car to be returned to original specification if required, with relative ease. Vintage Bentley have inspected many of the original chassis’ shortened  by H.M. Bentley, and have used this idea as a template for the Short Chassis 4½ Litre H.M. Bentley cars, Rebuilt to do a job well to build upon the creations of the mid to late 1930s Short Chassis cars by H.M. himself. 

While a 4½ Litre Bentley engine usually produces enough power for most applications, the Short Chassis isn’t made to drive like most other Bentleys. With the added handling prowess, the car can handle a much more powerful engine. The 4½ Litre engine receives a new, larger block to boost the horsepower and torque. A new rally differential is added to help transfer the power to the wheels along with a D type gearbox and modern clutch. Every moving part is upgraded to ensure the car will always be up for any challenge. The Short Chassis can reach 100mph with no struggle which proves useful on longer rallies and racing events.

To accompany the cars newfound power upgrades, the Short Chassis 4½ Litre H.M. Bentley requires stopping power and reliability to the same degree. The car is fitted with aluminium racing brake drums to shed weight and improve the braking distance, which is very much a necessity in a lightened 4½ Litre with more power than usual. Specially made reinforced radiators are equipped to fend off the environment during the most enduring rally adventures, and upgraded fuel tanks enhance reliability and fuel flow to feed the uprated engine with juice. Every detail comes from over a decade of preparing P2P cars, and is handled for maximum dependability when tackling whatever you can throw at the car.

As of present, the Vintage Bentley team have produced two Short Chassis 4½ Litre H.M. Bentleys. The two cars have endured over 40,000 miles of heavy use over 4 years, notable wins include the Benjafield’s 100 at Silverstone, competing in the Goodwood Revival Brooklands Trophy, and the 1000 Mile Trial. A testament to Vintage Bentley’s creation is a gratifying quote from an owner of one of the two existing Short Chassis 4½ Litre H.M. Bentleys, “This is the only car that has ever been delivered on time, on budget and has worked right out of the box”.

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