1939 Alvis Speed 25

The Alvis company was founded in 1919 by engineer T.G. John when he acquired the rights to an automobile engine and with it the brand name of its aluminum pistons – 'Alvis'. The first Alvis car, manufactured by T.G. John Ltd., was the 10/30 hp model of 1920. It was a conventional automobile that championed superb engineering and was one of the few light cars to utilize a four-speed gearbox. In 1922, newly appointed Chief Engineer Captain G. T. Smith-Clarke and Chief Designer W. M. Dunn created the immortal 12/50. Its new overhead-valve engine displaced 1,496cc and on its competition debut at Brooklands in 1923 secured a victory in the premier 200-Mile event. The winning car was driven by Major Maurice Harvey at an average speed of over 93 mph. The production version went on sale later that same year.

The six-cylinder Alvis 14.75 arrived in 1927 and its engine would serve as the basis for the long line of luxurious six-cylinder Alvis cars produced up to the outbreak of the Second World War. The Speed 20 with its 2,511cc engine arrived in 1932 and a year later, as the SB series incorporated several innovations including the world's first all-synchromesh gearbox and an independent front suspension. A larger 3,511cc engine arrived in 1936 with seven main bearings replacing the four of the earlier Speed 20, with an output of 110 horsepower. The vibration was minimized by balancing the clutch, flywheel, and crankcase together, and dual electric fuel pumps fed the three SU carburetors. The overhead-valve inline-6 was backed by a four-speed manual transmission, and drum brakes were placed at all four corners.

Initially, the 3 ½ litre model wore saloon bodywork only, but a year later it was joined with the latest version of the Speed 20 chassis resulting in the Speed 25. Alvis never built any of the bodies for the Speed 25, just the chassis. The majority of the coachwork was handled by Cross & Ellis who built the four-door tourer (39 examples), Charlesworth who built Drophead Coupes and Saloons (246 saloons were bodied by Charlesworth), and Vanden Plas. Additional coachbuilders included Lancefield, Offord, Carbodies, and Bertelli.

The Speed 25 was a more highly developed version of the 3.5-liter model and rested on a shorter 126-inch wheelbase. It used the same six-cylinder engine, although power had risen to 106 horsepower at 3,800 RPM. It had a balanced seven-bearing crankshaft, spring-cluster overhead valve gear, triple SU carburetors, and was backed by a four-speed, all-synchromesh gearbox. Improvements included a revised air-cleaner system and driver-controlled Luvax hydraulic shock absorbers. Stopping power was by large-diameter four-wheel servo-assisted brakes.

A total of four series of the Speed 25 left the Holyhead Road factory through 1940 with a total of 391 examples built. The Speed Twenty-Five's initial chassis-only price of £775 meant that ownership was necessarily confined to wealthy connoisseurs. At the time, the average U.K. house was around £550! Alvis built its last automobile in 1967

by Daniel Vaughan | Feb 2022