1934 Siddeley Special Sedanca Coupé Coachwork by Vanden Plas

Born out of the 1919 merger of Armstrong-Whitworth's car division with the Coventry-based Siddeley-Deasy, Armstrong-Siddeley was more noted for its automobiles' high quality of construction, rather than their outright speed. Nevertheless, the firm did produce one outstanding high-performance model in the 1930s - the 30hp Siddeley Special, which debuted in chassis form at the 1932 Motor Show at Olympia. The following year a Vanden Plas-bodied tourer took one of the concours prizes at the RAC Rally, and by the time manufacture ceased in January 1937 no fewer than 17 different coachbuilders had conceived bodies in a wide variety of styles for the 253 chassis produced, of which no more than 20 survivors are known to the Armstrong-Siddeley Owners Club.

Crafted in hiduminium alloy - a spin-off from the firm's aeronautical activities - the Special's magnificent six-cylinder overhead-valve engine produced 125bhp at 3,200rpm. A seven-bearing design displacing 5.0 litres, this paragon of power units transmitted its abundance of low-speed torque via a Wilson pre-selector gearbox, and could propel the heavyweight Special smoothly from walking pace to over 90mph in top gear.

The Special's blend of engineering excellence and a performance to match Bentley's 'Silent Sportscar' guaranteed its appeal, though the high price meant that ownership was necessarily restricted to a wealthy elite, Sir Malcolm Campbell and Tommy Sopwith among them. Nevertheless, its blend of performance and quality must have been of some concern to Rolls-Royce.

Source: Conceptcarz, Wikipedia, Bonhams, other