Armstrong Siddeley was formed in 1919 when Armstrong Whitworth (q.v.) acquired Siddeley-Deasy (q.v.). Vickers bought out the holding company, John Siddeley bought out the car and aircraft businesses.
Armstrong Siddeley became synonymous with high-quality engineering and Sphinx-like silence. They famously pioneered the Wilson pre-selector gearbox, which simplified gear changes for luxury owners. Their pre-war pinnacle was the 1932 Siddeley Special, featuring a lightweight aircraft-alloy engine. This aviation heritage defined the marque’s reputation for precision up to the Second World War.
Armstrong Siddeley 30
Very large car but good value. 2-wheel brakes and twin inline blocks until 1925. Wilson preselector from 1928. Aero-engine heritage showed in the use of aluminium.
Years
1919-31
Engine
4960cc S6
Body Style
Various
Production
2770
Power: Weight
.
Dimensions
.
Photo: ASHT
Armstrong Siddeley 18
Scaled-down 30 for two-thirds the cost. 18/50 or MkII from 1925. Long version available for limousine bodywork in 1926.
Years
1921-26
Engine
2380cc/2872cc S6
Body Style
Various
Production
2500
Power: Weight
.
Dimensions
.
Photo: Flickr
Armstrong Siddeley 14/4 (14/30)
Economy model with just four cylinders, suited to the times, but still well built. Flat radiator, reminiscent of the Stoneleigh sub-brand (q.v.) which it effectively replaced.
Years
1923-29
Engine
1852cc S4
Body Style
.
Production
13,365
Power: Weight
.
Dimensions
.
Photo: Flickr
Armstrong Siddeley 20
Replaced the 18, and was an important model, appealing to professional classes, and becoming the firm’s best seller. Underslung chassis and centralised lubrication from 1928.
Years
1926-36
Engine
2872cc
Body Style
Short/long
Production
8847
Power: Weight
.
Dimensions
.
Photo: Flickr
Armstrong Siddeley 15; 15/6
Upgraded 14 – although a reversion to side-valve, which fashionable at the time. Traditional AS radiator grille from 1930. Quiet, smooth and flexible.
Years
1927-29; 1929-34
Engine
1900cc S6 (2169cc from 1933)
Body Style
Tourer, saloon, sports
Production
7203
Power: Weight
.
Dimensions
.
Photo: CSC
Armstrong Siddeley 12
The smallest Armstrong Siddeley. Helped start of trend for small displacement straight six. Mole or maroon. Even had the pre-selector gearbox from 1931. Vee-radiator from 1934.
Years
1929-37
Engine
1236cc S6 (1434cc from 1931)
Body Style
Tourer, saloon, sports
Production
12,500
Power: Weight
.
Dimensions
.
Armstrong Siddeley – Siddeley Special
One of the ultimate pre-war cars, and John Siddeley’s swansong. Choice of wheelbases. Hiduminium alloy (as newly developed by Rolls-Royce for aviation) engine. Fluid flywheel option paired with the pre-selector. High-speed cruiser.
Years
1933-37
Engine
4960cc S6
Body Style
Tourer, saloon, limousine
Production
253
Power: Weight
.
Dimensions
.
Photo: Flickr
Armstrong Siddeley 17
OHV replacement for the 15. Usual AS refinement. Lots of body styles – short: coupé, saloon, sports saloon; long: saloon, tourer, Atalanta sports saloon, limousine, landaulette.
Years
1935-39
Engine
2394cc S6
Body Style
Short/long
Production
4260
Power: Weight
.
Dimensions
.
Photo: Flickr
Armstrong Siddeley (12 Plus;) 14
Bigger and heavier replacement for the 12, largely based on the 17.
Years
1936-39
Engine
1666cc S6
Body Style
Saloon, tourer
Production
3750
Power: Weight
.
Dimensions
.
Photo: Flickr
Armstrong Siddeley 20/25
Enlarged 20 on choice of two wheelbases – the short ones can do 80 mph – the longer are hightly refined. Excellent build quality as usual. Outlived the Special, and took the top end of the range up to WWII.
Years
1936-40
Engine
3670cc
Body Style
Saloon, tourer, Atlanta sports saloon Limousine, landaulette
Production
884
Power: Weight
.
Dimensions
.
Photo: Bonhams
Armstrong Siddeley 16
More modern take on the mid-range car, designed to replace the 17. Platform (near unitary) chassis. Its 1.9-litre was heavily influenced by the company’s aviation expertise, featuring water-cooled valve ports and combustion chambers.
Years
1938-41
Engine
1991cc
Body Style
Saloon, Sports saloon
Production
950
Power: Weight
.
Dimensions
.
Photo: Flickr