| Manufacturer | Alvis |
|---|---|
| Production | 1937–1940 |
| Predecessor | Alvis Speed 20 |
| Class | Touring car |
| Body style | cabriolet (generally – delivered only as a chassis) |
| Engine | 3.5-litre Straight-6 |
The Alvis Speed 25 was a British touring car made between 1936 or 1937 and 1940 by Alvis Ltd in Coventry. It replaced the Alvis Speed 20. The earlier car’s six-cylinder, four main bearing engine was replaced in the Speed 25 with a similarly designed larger six-cylinder in-line unit with seven main bearings for which an output of 110 PS at 3,800 rpm was claimed, along with a top speed of almost 160 km/h (100 mph).[1]
The clutch, fly wheel and crankshaft were balanced together, which minimised vibration. The cylinder head was of cast iron but the pistons were of aluminium.[1] Two electric petrol pumps fed the three SU carburettors, which were protected by a substantial air filter.[1]
Alvis never supplied any of the bodies for the Speed 25; the cars were supplied in chassis form and firms such as Cross & Ellis (standard tourer) Charlesworth (standard saloon and Drop Head Coupé) as well as Vanden Plas, Lancefield and others would fit suitably elegant open touring or saloon car bodies.[1] The car was built on a heavy steel chassis with a substantial cross brace. With its sporty low slung aspect, all-synchro gearbox, independent front suspension and servo-assisted brakes, this was a fast, reliable and beautifully made car, although at almost £1000 it was not cheap. The survival rate for what was after all a hand-built car is surprisingly good. Later models featured increased chassis boxing, and to reduce the car’s weight Alvis cut numerous holes in the chassis box sections, which was also a solution tried less successfully earlier in the decade by Mercedes-Benz when confronting the same challenge with their enormously heavy Mercedes-Benz SSKL.[1]