The Vauxhall 20 h.p. chassis code A, was a four-cylinder medium-sized car manufactured by Vauxhall from 1908 to 1914 with one more built in 1920. It was the first production Vauxhall designed by Laurence Pomeroy. It became a highly acclaimed 3 litre of its day and at Brooklands on 26 October 1910 it became the first 20 hp car to exceed 100 mph (160 km/h).[citation needed]

Vauxhall 20 22 and 16-20
A
22.4 horsepower A12 3½-litre, 1912
Overview
ManufacturerVauxhall
ProductionOctober 1908 to 1915
AssemblyLuton Bedfordshire
DesignerLaurence Pomeroy
Powertrain
Engine4-cylinder inline
186 cu in (3,054 cc)
208 cu in (3,402 cc)[1]
Transmissionmanual: 4-speed and reverse
(some early cars 3 speed)
clutch
early cars— cone
later cars— multi-plate in graphite
final drive by—[1]
Dimensions
Wheelbase2,921.0 mm (115 in)
3,124.2 mm (123 in)[1]
Lengthwidth and height depending on coachwork
Kerb weightdepends on coachwork
Vauxhall 20 and 22
A
Overview
ManufacturerVauxhall
Layout
Configurationin-line 4-cylinder
Displacement3054 c.c.
(3½-litre 3402 cc)
Cylinder bore90mm
(3½-litre 95mm)
Piston stroke120mm
Cylinder block material
Sheet copper sump in very early cars, later cast alloy[1]
Valvetraincamshaft gear-driven until 16-20 was driven by chain[1]
Combustion
Fuel systemCarburettors:
White & Poppe
Zenith
Claudel Hobson
gravity or forced feed[1]
Fuel typepetrol
Cooling systemthermo syphon
Output
Power output1909 38 bhp (28 kW; 39 PS)
1910 60 bhp (45 kW; 61 PS)
1913 80 bhp (60 kW; 81 PS)
tax horsepower:
3054cc 20.09hp
3402cc 22.38hp[1]
Early 16-20 engine
16-20 h.p. 1914
16-20 h.p. 1914 with racing body

Genesis

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Laurence Pomeroy had joined Vauxhall in 1907 as an assistant draughtsman at the age of twenty-two. He first made his mark at the 1908 RAC and Scottish Reliability Trial, held in June of that year. His first prototype, a development of Vauxhall's 12-16 and named Y1, had outstanding success showing excellent hill climbing ability with an aggregate of 37 seconds less time in the hill climbs than any other car in its class and unparalleled speeds around the Brooklands circuit. His Vauxhall was so far ahead of all cars whatever class that the driver could relax, accomplishing the 200 miles (320 km) at an average speed of 46 mph (74 km/h), when the car was capable of 55 mph (89 km/h). It went on to win class E of the Trial. That design was put into production in 1908 as Vauxhall's 20 hp offering. Four distinct variations were produced between 27 October 1908 and the end of production in 1914. One last car was put together in 1920.[1]

The four distinct versions - A09, A11, A12 and 16-20

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Engine

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The 3-litre side-valve monobloc engine was provided with forced lubrication . The camshaft and magneto were gear-driven until the 16-20 when it was changed to chain drive.[1]

Reviewing the exhibits at the North of England Motor Show at the beginning of 1912 the Manchester Guardian reported that the 20 h.p. engine had been given for 1912 new light connecting rods of very high grade steel and pistons reduced in weight to give smooth running.[2]

Gearbox

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The A09 and A11 were supplied with a four-speed gearbox though some of the earliest cars retained the three-speed gearboxes of the 12-16 and at least 70 of the first cars also retained the sheet copper sump of their predecessor. There was a major revision of the chassis for the A12 and for the 16-20 both engine and chassis underwent major redesign.[1]

 
A12 3½-litre, 1912
 
Sutherland cabriolet 1912

Range for 1913

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In November 1912 immediately before the opening of the Olympia Show Vauxhall announced their full range for 1913 would be four chassis:

  • 16-20 hp 4-cylinder 90 x 120 mm chassis £395
  • 25 hp 4-cylinder 95 x 140 mm chassis £465 (replaces the 20 hp)
  • 25 hp Prince Henry chassis £495
  • 35 hp six-cylinder 95 x 120 mm chassis £625

all were to have 4-speed gearboxes[3]


See the table[1] below for more information.

20 hp
A09
20 hp
A11
20 hp
A12
22 hp
A12
16-20 hp
A12
Production run:
253 cars
359 cars
57 cars
21 cars
271 cars
Period:
Oct 1908 - Oct 1910
Oct 1910 - Jun 1912
Jun 1912 - Nov 1912
Nov 1912 - 1915
Oct 1920 (one car)
Work Orders:
1770–1778
1803–1811
1811 & 1812
1813–1818
Engine:
Capacity
Bore x Stroke
-

3 Litre

90 x120
-
3 Litre 90 x120
-
3 Litre 90 x120
-
3½ Litre 95 x120
-
3 Litre 90 x120
Carburettor:
White & Poppe
Zenith
Claudel Hobson
-
30 mm

-

-

-
30 mm

-

-

-
30 mm
36 mm

-

-
30 mm
36 mm
26 mm
Fuel supply:
gravity
gravity
gravity a few forced feed
forced feed
Cam drive:
gear
gear
gear
chain
Magneto:
Bosch D
Bosch D
Bosch D
Bosch D or Eisman EK4
Clutch:
cone
cone or multi-plate
multi-plate
multi-plate
Brake drums:
12 inches (300 mm)
12 inches (300 mm)
12 inches (300 mm)
9 inches (230 mm)
Rear axle ratio:
1:2.95 to 1:4.13
1:3.65 or 1:3.875
1:3.65 or 1:3.875
1:3.875
King pins:
vertical
vertical
inclined
inclined
Std Wheel size:
875 x105 mm
875 x105 mm
880 x120 mm
815 x105 mm
Sub frame
U section
U section
angle iron
angle iron
Chassis length:
9 ft 7 in (2,920 mm) or 10 ft 3 in (3,120 mm)
9 ft 7 in (2,920 mm) or 10 ft 3 in (3,120 mm)
9 ft 7 in (2,920 mm) or 10 ft 3 in (3,120 mm)
9 ft 9 in (2,970 mm)
Chassis width:
Front:
Rear:
-
30 inches (760 mm) 36 inches (910 mm)
-
30 inches (760 mm) 36 inches (910 mm)
-
30 inches (760 mm) 36 inches (910 mm)
-
28 inches (710 mm) 34 inches (860 mm)

Capable of up to 100 mph (160 km/h) the A-Type Vauxhall was one of the most acclaimed 3-litre cars of its day,[citation needed] achieving many records for out-right speed and high speed endurance, within the 21 hp limit, as well as having had some parental involvement in the conception of both the Prince Henry and the 30-98 Vauxhalls.[1]

Fewer than two dozen survive today out of the 950 produced.[1]

Basic chassis changes during production[1]

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Model Date Range Chassis Change Work Order Car Number / Range of Car Numbers Change
16-20 21 Nov 1912 to
2 Oct 1920
1813–1818 For the 16-20 A-Type Laurence Pomeroy introduced a completely new chassis design. With the first work order for 16-20 cars 1813 the chassis had changed quite considerably. The 16-20 A-Type Work Order 1813 Chassis was drawn up in May 1912 Drawing Number: No663-664 Drawing Date: 19-05-1912. The chassis narrowed at the front and rear to Front: 28 inches Rear: 34 inches.
1813–1818 Sometime in 1913 the clutch, transmission brake and accelerator pedal design changed somewhat.
16-20 16 Aug1913 1814 For the 1814 work order the chassis was redesigned again to
20 Sep 1913 - onwards 1814 A58-A104 Sometime between A58 and A104 the support brackets for the running boards changed from a bracket secured by 2 large dome headed bolts to a bracket fixed with 4 smaller bolts. The newly designed brackets slowly were fitted as stocks diminished of the 2 bolt type.

Engine changes during production[1]

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Model Date Range Engine Change Work Order Engine Number / Range of Engine Numbers Change
A09 xx xxx 1908 1770–1778 The A09...
24 Nov 1908 to

25 Jun 1909

1770–1771 A09.01-A09.73 Sometime between A09.1 and A09.73 the engine sump was changed from a sheet copper sump carried over from the X Type Engine to a Cast Alloy sump.
A11 xx xxx 1908 1803–1811 The A11...
A12 xx xxx 1908 1811–1812 The A12...
16-20 21 Nov 1912 1813–1818 The 16-20...

For the 16-20 A-Type Laurence Pomeroy introduced a completely new engine design with a silent chain drive for the cam-shaft and magneto. The inlet manifold is now cast en bloc with the radiator cooling outlet pipe located at the front where the fan bolts on this was to allow a waterpump to be fitted if required.

6 Mar 1913 to 26 Jun 1913 1813-1813 A8-A31 Sometime between Engine Numbers A8 and A31 the exhaust manifold gained cooling fins located along the top of the manifold.
26 Jun 1913 to 12 Mar 1914 1813–1814 A31-A41 Sometime between Engine Numbers A41 and A100 the external oil level pot located on the side of the engine sump carried over from A09-A12 Production was deleted in favour of a redesigned sump integrating this feature.
26 Jun 1913 to

12 Mar 1914

1813–1816 A31-A100 Sometime between Engine Numbers A31 and A100 the radiator outlet located around the fan on the engine block was relocated to the side of the block near the front under the inlet manifold.
29 Sep 1913 to 12 Mar 1914 1813–1816 A41-A100 Sometime between Engine Numbers A41 and A100 the external oil feed line going to each main bearing in the crank case was deleted in favor of an oil gallery integral to the crank case.
12 Mar 1914 to

5 May 1914

1816–1817 A100-A151 Sometime between Engine Numbers A100 and A151 the number of securing bolts holding the radiator inlet on top of the engine block increased from 4 bolts to 6 bolts.
12 Mar 1914 to

5 May 1914

1816–1817 A100-A151 Sometime between Engine Numbers A100-A151 the steel baffles located under the cylinders in the engine block were deleted from production.

Surviving cars[1]

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Model Year Chassis Number Work Order Engine Number Gearbox Number Steering Box Number Radiator Number Cooling Petrol Supply G.Gravity F.Force Magneto Carburettor Hand Brake Dia Size of Tyre Rear Axle Ratio Date of Manufacture Location Status Body Type
A09 1908 A09.1 1770 A09.1 Thermo Syphon G Bosch D W+P 30mm 12" 875x105 15-62 24-11-1908 Australia Restored
A09 1909 A09.73 1771 A09.73 Thermo Syphon G Bosch D W+P 30mm 12" 875x105 17-56 25-06-1909 England Restored
A11 1911 A11.455 1808 A11.455 Thermo Syphon F Bosch D W+P 30mm 12" 875x105 16-62 29-09-1911 Spain Restored
A11 1911 A11.487 1808 A11.471 Thermo Syphon G Bosch D W+P 30mm (Current Engine from A11.471 had Zenith 36mm) 12" 880x120 16-62 7-11-1911 Australia Restored
A11 1911 A11.596 1811 A11.440 Thermo Syphon F Bosch D W+P 30mm 12" 875x105 16-62 5-02-1912 Australia Restored
A12 1912 A12.670 1812 A12.670 Thermo Syphon G Bosch D Zenith 36mm 12" 875x105 16-62 23-08-1912 Australia Restored
A12 1912 England N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
16-20 1913 A13 1813 A8 N/A N/A N/A Thermo Syphon F Eiseman EK4 Zenith 36mm 9" 815x105 16-62 6-03-1913 New Zealand Unrestored
16-20 1913 A35 1813 A31 121 1517 31 Pump F Eiseman EK4 Zenith 36mm 9" 880x120 16-62 26-06-1913 Australia Under Restoration
16-20 1913 A58 1814 A151 N/A N/A N/A Thermo Syphon F Eiseman EK4 Zenith 36mm 9" 880x120 16-62 20-09-1913 Australia Restored Ascot 2 seat (original)
16-20 1914 A104 1816 A100 380 N/A N/A Thermo Syphon F Bosch ZR4 Zenith 36mm 9" 815x105 16-62 12-3-1914 New Zealand Unrestored
16-20 1914 A170 1818 A186 704 N/A 1601 N/A N/A N/A Claudel Hobson 26mm 9" 880x120 15-62 01-12-1914 Australia Restored
16-20 1914 A198 1817 A192 N/A N/A N/A N/A N/A Bosch ZR4 Claudel Hobson 26mm 9" 815x105 16-62 24-11-1914 England Restored
16-20 1914 A207 1817 A197 N/A N/A N/A Thermo Syphon F Eiseman EK4 Claudel Hobson 26mm 9" 880x120 16-62 8-12-1914 Australia Unrestored
16-20 1914 A210 1817 A207 N/A N/A N/A Thermo Syphon F Bosch ZU4 Claudel Hobson 26mm 9" 875x105 16-62 23-10-1914 Australia Restored
16-20 1914 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A

References

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  1. ^ a b c d e f g h i j k l m n o p From little acorns mighty oaks grow, Alisdaire Lockhart, May 2004. The A Type Vauxhall Register Archived 19 February 2013 at the Wayback Machine
  2. ^ Some Exhibits: Vauxhall. pg 5. The Manchester Guardian; 20 February 1912;
  3. ^ page 1283, The Automotor Journal 2 November 1912