The events leading up to the acquisition of Bentley Motors by Rolls-Royce in 1931, and the development of the new car, were set out very clearly in WOBMF Chairman Ken Lea’s definitive article in issue one of 1888 published by the Foundation. The Derby was a development of the planned small Rolls-Royce, codenamed Peregrine II. This was to have been an owner-driver car of 2.3 litres engine capacity. Five prototypes were completed in 1932, on an excellent, nicely proportioned chassis, and capable of over 70mph. Its downfall, however, was that it would have been too expensive to make such a car in the 18hp class when built to standard Rolls-Royce philosophies. Because of this it was later abandoned.

When Rolls-Royce Managing Director Arthur Sidgreaves spotted an opportunity for a sporting car of about 3 litres capacity, early schemes duly centred around versions of the Peregrine engine in various guises, but which were aborted for being too time-consuming. However, it was the decisive intervention of Ernest Hives, head of the experimental department, who suggested that an engine from another abandoned project would be the ideal unit to use. His idea was adopted, albeit in twin carburettor form and using a cross-flow cylinder head, and the engine (codenamed Japan) formed the basis of the very first Derby prototype, aka

This maiden prototype (1-B-III) was clothed with a close-coupled Park Ward saloon body and sported a delightful WO-style radiator mascot. In this form, it was taken to West Wittering where Royce saw it. It was then tested at over 90mph at Brooklands. In his report, dated 6 February 1933, WO famously stated: “I would rather own this Bentley than any car produced under that name”. Shortly afterwards, 1-B-III was tested in France where it achieved a maximum speed of 96mph at Montlhery racetrack. After a punishing test programme, the prototype was dismantled, although the body and some running gear were transferred to a second chassis 1-B-VI) fitted with a new engine and the 20/25 gearbox. By April 1933, when the next prototype (2-B-IV) was built, the mechanical specification had been largely settled. This car also had a saloon body and was initially fitted with flared wings.

The Derby’s maximum speed was tested at just 85.43mph while comparative tests were made involving an Alvis Speed 20 (80.5mph) and its other obvious competitor, the Talbot  95 (82.31mph). Although faster than these rivals which had smaller engines, the car’s top speed was disappointing. Its flared wings were therefore removed and replaced with domed versions resulting in a top speed well in excess of 90mph –
leading to the adoption of enclosed front wings. After some refurbishment that car was made available to WO before being renumbered as B-100- BN and sold to the tyrannical Trevor Westbrook of Vickers-Armstrongs. The car was last recorded in Canada in the 1970s and may now be lost. After rigorous further testing of prototypes, four Derbys were photographed in August 1933 at the Aldenham House country club in Elstree. The cars, constructed to production specification, were then made available to the press at the Royal Ascot Hotel in October. Geoffrey Smith of The Autocar tested the last of the original prototypes (4-B-IV) which was registered as RC1351 and sported a light Park Ward three-door tourer body, later transferred to a production chassis. Smith reported the car’s total weight at just 28cwt, resulting in top speeds of well over 90mph. Like all the press reports, Smith’s write-up (6 October) was glowing in its praise. Even at £1,380 for an open tourer (twice the cost of an open Alvis Speed 20 of 2.5 litres), this new Derby was destined to sell like hot cakes. Unlike earlier Bentleys, and the products of many other sporting marques, there was always only one specification at any one time; the only differences were spring settings, spare wheel mounting arrangements and minor changes as specified by the customer.

The speeds achieved by these sports cars were very high for their day and continued to be competitive 20 years later when in the hands of their second and third owners. They remained the ‘musthave’ machine for the sporting motorist, often in preference to the early post-war cars which evolved from them but which had a notably less sporting character. I have had the privilege of owning three Derbys, all of 3½ litres but each with a different body style and character. Everything was just so superbly made that you cannot help but respect the makers who were determined to build the best chassis possible with the (considerable) resources available to them. The proof of the Derbys’ success lies in their extraordinary survival rate, believed to be 75 per cent



Derbys and Rolls-Royces emerged from the same production lines, built to the same standard and with the same extraordinary attention to detail. At the time the Derby was being developed, many great marques went to the wall or were taken over and their products debased. The Derby-built cars do have their sensitivities sometimes exacerbated by a lack of proper servicing and attention, but there’s no doubt they re-established the Bentley name and afforded it a secure future – which duly allowed it to form the bedrock of post-war Crewe production. I am indebted to Ken Lea for his help with this article and Rolls- Royce and Bentley Experimental Cars by Ian Rimmer.


The launch cars at the Park Ward works in Willesden in August in 1933



All Derby owners and their cars are invited to celebrate the Derby’s 90th anniversary at a special rally in Cheshire and Derbyshire organised by Neill Fraser and the Silent Sports Car Club next September.

-See December’s Advertiser & Diary for details.

Derbys celebrating their 70th anniversary at Chatsworth House in September 2003


Written by Richard Edgell. Images: Courtesy of WOBMF and Neill Fraser

Thank you to the Bentley Drivers Club (BDC) for giving us kind permission to use this article on our website.

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