Alvis Speed 20 History
A fast, elegant six-cylinder tourer — the first car with an all-synchromesh gearbox (1933) and independent front suspension on the SB.
Photo: “1932 Alvis Speed 20A Sport Tourer - fvlL.jpg” by Rex Gray from Southern California / Wikimedia Commons, licensed under CC BY 2.0
History
Announced in late 1931, the Speed 20 used a six-cylinder engine derived from the Silver Eagle but heavily modified to produce around 87 bhp, giving a genuinely fast and refined sporting car bodied by leading coachbuilders such as Vanden Plas and Charlesworth.
The Speed 20 carried two landmark Alvis innovations. The 1933 SB introduced the world's first all-synchromesh gearbox — synchromesh on all gears — together with independent front suspension via a transverse leaf spring. For 1935 the SC grew the engine to 2,762 cc, and the SD of 1936 added a larger fuel tank and slightly wider bodywork.
About 1,165 Speed 20s were built across the SA, SB, SC and SD variants before it was replaced by the 3.5-litre Speed 25 in 1937.
Generations
SA
Photo: “1932 Alvis Speed 20A Sport Tourer - fvlL.jpg” by Rex Gray from Southern California / Wikimedia Commons, licensed under CC BY 2.0
The original 2,511 cc six producing about 87 bhp; roughly 400 built.
1932 Photo: “1932 Alvis Speed 20 SA.jpg” by Calreyn88 / Wikimedia Commons, licensed under CC BY-SA 4.0
1933 Photo: “1933 Alvis Speed 20 Saloon SA.jpg” by Calreyn88 / Wikimedia Commons, licensed under CC BY-SA 4.0
SB
Introduced the world's first all-synchromesh gearbox and independent front suspension; engine raised to about 95 bhp.
1933 Photo: “1933AlvisSpeed20SB.jpg” by dave_7 / Wikimedia Commons, licensed under CC BY 2.0
1934 Photo: “1934 Alvis Speed 20 SB "flat-back" 2-door saloon by Vanden Plas, front left.jpg” by Mr.choppers / Wikimedia Commons, licensed under CC BY-SA 3.0
SC
Engine enlarged to 2,762 cc by lengthening the stroke.
1935 Photo: “1935 Alvis Speed 20 SC by Charlesworth 2.8.jpg” by Vauxford / Wikimedia Commons, licensed under CC BY-SA 4.0
SD
Final 2,762 cc version with a larger fuel tank and slightly wider bodywork.
1936 Photo: “1936 Alvis Speed Twenty SD 9335483141.jpg” by Graham Robertson / Wikimedia Commons, licensed under CC BY 2.0
Body styles
- Sports tourer
- Drophead coupé
- Sports saloon
Related models
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