Bentley 4.5 Litre Le Mans Special

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The famous Bentley make, erected by Mr. W.O. Bentley, existed as a independent firm for only twelve years (1919-1931) before the proud firm was taken over by the Rolls Royce motor company.
Those twelve exhilarating Bentley years were filled with racing successes and many victories. The Bentley name as manufacturer of large, heavy, powerful and rugged sportscars was imprinted in the human mind since the "roaring" twenties of the twentieth century.
Bentley motorcars won the famous 24 hours of Le Mans race in the years 1924, 1927, 1928, 1929 and 1930. The years they did not win the race they finished second or third.
Not only successes at Le Mans were counted but also many victories in the Brooklands 500 mile race.
The car presented here is a "Petersen Special" inspired on the Bentley 4.5 Litre which won at the Brooklands circuit in the year 1929.
De Bentley 4.5 Litre racing cars brought victories for Bentley in the years 1928 and 1929. These cars featured Van den Plas open tourer bodywork and the all British Racing Green colour scheme.

In the picture below you see a ghost drawing of the Bentley blower 4.5 Litre (Le Mans 1928 winner) on the left and a photograph of the Bentley 4.5 Litre (1929 Brooklands 500 mile race winner).

To obtain more engine power Bentley added a blower (sipercharger) to the 4.5 litre in-line four cylinder engine. This increased power output from approx. 110 bhp. up to 240 bhp. maximum.
To get the Bentley 4.5 Litre blower accepted in racing at Le Mans Bentley had to built fifty production cars first. Twenty six of these cars were built with Van den Plas open tourer bodywork.
 The addition of the supercharger did not make the rugged and reliable 4.5 litre engine any more trustworthy during races. W.O. Bentley himself preferred a new engine with increased cylinder capacity.  The supercharged 4.5 Litre engines were real "gas-guzzlers", the naturally aspirated 4.5 Litre engine used one litre of petrol every 5.6 kilometres, the supercharged engine used one litre for just 3.5 kilometres, a very large petrol tank was fitted additionally.
Another problem was that spark plugs in the supercharged engine wore out very quickly resulting in loss of power. Bentley engineer Nobby Clarke stated one day: "The blower eats spark plugs like a donkey eats hay"...
The Bentley 4.5 Litre Le Mans racer, with blower or without, is one of the top classic cars you can possibly dream to own. Collectors pay very high prizes for these, very scarce, Bentley racing cars.
Because the cars are very scarce and many people want to own one, many other Bentley models were modified to Le Mans specification and many replica's became available.
Sales prices of modified Bentley's and replica's are a fraction of the price asked for the real thing.
Talking about Bentley Le Mans replica's the specials built with Petersen bodywork and special manufactured parts are the finest around in quality and integrity. Much of the final quality however is in the hands, patience and precision of the private person or specialist who builds the automobile.
The featured Bentley 4.5 Litre Le Mans tourer Special is certainly one of the finest. This Bentley Special was built with love and care to absolute perfection.

Technical data

Engine: six cylinder Bentley engine, modified
Cylinder capacity: 4.9 Litre
Carburettors: 2 x S.U. HD 6 1¾ inch.
Petrol system: electric SU fuelpump, airpress by
handpump located on the dashboard
Petrol tank: 150 litres
Ignition: AC Delco 2-5 degrees BTDC 
Capacity: 175 bhp. (road specification.)
Gearbox: Bentley MK VI with Laycock overdrive
Clutch: Bentley MK VI modified to hydraulic operation
Chassis: 1935, Rolls Royce 20/25 modified
Front axle: Rolls Royce 20/25 with André Hartford friction
type adjustable dampers assisted by Spax adjustable telescopic units
Rear axle: Rolls Royce 20/25 with modified 20/25
hydraulic dampers
Springs: Reprofiled Rolls Royce 20/25 bound
Brakes: Fully hydraulic with Lockheed servo assistance
Wheels: 4½ inch x 19 inch, 70- spoke wires
Electrical: 12 volt negative earth
Bodywork: Two door Van den Plas four seater replica,
aluminium over ash wood frame
Hood: Stainless steel hood frame, double duck hood
and tonneau cover
Interior trim: green Wilton carpet and green Connolly leather
Weight: approx. 1900 kg.


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