Austin 12 hp

Austin Twelve 1660 cc & 1861 cc
Twelve (wide track) with fabric saloon body c. 1928
Overview
Manufacturer	Austin
Production	1921–1939 88,000
Body and chassis
Body style	catalogued: tourer, saloon, sports coupé, Harley all-weather tourer, fabric saloon special chassis for various—hire car, taxi, London taxi, van and other commercials
Powertrain
Engine	1660 or 1861 cc Straight-4
Transmission	single-plate clutch, 4-speed centrally controlled gearbox, linked by disc coupling to the open propellor shaft, by metal universal joint to a helical bevel driven live rear axle. The clutch housing is cast in one with the gearbox.
Dimensions
Wheelbase	9' 4", 112 in (2,800 mm) Track 4' 4", 52 in (1,300 mm) 4' 8", 56 in (1,400 mm)
Length	13' 6", 162 in (4,100 mm)
Width	5' 3", 63 in (1,600 mm)
Kerb weight	Chassis 16¼ cwt, 1,820 lb (830 kg) tourer 22 cwt, 2,464 lb (1,118 kg) saloon 24 cwt, 2,688 lb (1,219 kg)
Chronology
Predecessor	Austin Ten-Twelve
Successor	none

Austin Twelve engine 1660
Overview
Manufacturer	Austin
Combustion chamber
Configuration	Straight 4-cylinder
Displacement	1,660 cc (101 cu in)
Cylinder bore	72 mm (2.8 in)
Piston stroke	102 mm (4.0 in)
Cylinder block alloy	cast iron, alloy crankcase. The inlet manifold is cast in one with the cylinder head
Cylinder head alloy	detachable, pistons are aluminium
Valvetrain	side-by-side valves, tappet covers may be easily removed, timing is driven by chain
Combustion
Fuel system	single carburettor supplied by a vacuum tank which draws from a reservoir beneath the driver's seat, ignition by magneto driven by chain placed behind the timing, dynamo driven by same chain
Management	back seat
Fuel type	petrol
Oil system	lubrication by forced feed, filler on the offside
Cooling system	radiator, fan, cooling water is circulated by a pump forward of the timing on the nearside
Output
Power output	20 bhp (15 kW; 20 PS) @2,000 rpm Tax horsepower 12.8
Chronology
Successor	Austin Twelve 1861 cc

The Austin Twelve is a motor car that was introduced by Austin in 1921. It was the second of Herbert Austin's post World War I models and was in many ways a scaled-down version of his Austin Twenty, introduced in 1919. The slower than expected sales of the Twenty brought about this divergence from his intended one-model policy. The Twelve was announced at the beginning of November 1921 after Austin's company had been in receivership for six months. The number twelve refers to its fiscal horse power (12.8) rather than its bhp which was 20 and later 27. The long stroke engines encouraged by the tax regime, 72 x 102 later 72 x 114.5, had much greater low speed torque than the bhp rating suggests.

Initially available as a tourer, by 1922 three body styles were offered, these being the four-seat tourer, the two/four-seater (both at 550 GBP) and the coupé at 675 GBP.

The car enjoyed success throughout the vintage era with annual sales peaking at 14,000 in 1927.

While the mechanical specification changed little (the engine increased from 1661 cc to 1861 cc in 1926), many body styles were offered with saloons becoming more popular as the twenties drew to a close.

The car continued in the Austin catalogue and as a Taxi option until 1939. The last cars were produced for the War Department in 1940.

After the early thirties the car was referred to by the public as the Heavy Twelve to distinguish it from the other, newer, 12HP cars in the Austin catalogue Light Twelve-Four, Light Twelve-Six etc. and received some updating. The artillery style wheels were replaced by wire wheels in 1933 and coil ignition replaced the magneto in 1935. The gearbox was provided with synchromesh between its top two ratios in 1934. The factory catalogued body range was steadily updated with the last of the no longer fashionable Weymann style fabric covered cars in 1931 and no open tourers after 1934.