click here to view more info

Specifications:

  • Six cylinder in-line engine
  • Monobloc cylinder block
  • Bore x stroke 3 x 4 1/2 in
  • Capacity 3,127 cc
  • Push-rod operated valves located in detachable cylinder head
  • Aluminium alloy crankcase
  • Stand-by magneto standard
  • Dry-plate type clutch
  • Three-speed gearbox with centre gear change from 1925 4-speed-gearbox with right-hand gear lever
  • Semi-elliptic springs front and rear
  • Rear wheel brakes from 1925 4-wheel brakes, servo-assisted
  • Wheelbase 129 in
  • Track 54 in, from 1925 track 56 in
  • Tyre size 32 x 4 1/2 in

History:

Rolls-Royce codenamed the vehicle Goshawk and it was easily recognizable by its horizontally arranged radiator shutters. The last series though had vertical shutters.

A shorter wheelbase and a more economical engine proved an ideal addition to Rolls-Royce’s range.

Its lighter weight and a reduced turning circle gave the 20 hp good handling.

The model was built between 1922 and 1929 and was produced alongside the 40/50 Silver Ghost and Phantom. It was intended to appeal to owner-drivers but many were sold to customers with chauffeurs.

A new inline-6 cylinder overhead valve engine was designed and unlike the Silver Ghost, the cylinders were cast in one block and the cylinder head was detachable.

Both coil and magneto ignitions were fitted. The early cars had 3-speed manual gearboxes with the change lever in the centre of the car, but this changed in 1925 to a four-speed unit with traditional right-hand change.

The substantial chassis had rigid front and rear axles suspended by half-elliptic springs, with braking initially only on the rear wheels. Four-wheel brakes with mechanical servo were introduced in 1925.

The famous Rolls-Royce radiator with triangular top was fitted, and early examples had enamel-finished horizontal slats, later changing to a nickel finish and finally becoming vertical.

Only the chassis and mechanical parts were made by Rolls-Royce. The body was made and fitted by a coachbuilder selected by the owner.

Some of the most famous were Barker, Park Ward, Thrupp & Maberly, Mulliner and Hooper.

Sources: Rolls-Royce, The Rolls-Royce Twenty by J Fasal

Restoration information:
Information to come.

Concours/show results:
Information to come.