The Rolls-Royce 30 hp was one of four cars to be produced as a result of an agreement of 23 December 1904 between

Charles Rolls Charles Stewart Rolls (27 August 1877 – 12 July 1910) was a British motoring and aviation pioneer. With Henry Royce, he co-founded the Rolls-Royce Limited, Rolls-Royce car manufacturing firm. He was the first Briton to be killed in an aeron ...

and

Henry Royce Sir Frederick Henry Royce, 1st Baronet (27 March 1863 – 22 April 1933) was an English engineer famous for his designs of car and aeroplane engines with a reputation for reliability and longevity. With Charles Rolls (1877–1910) and Claude J ...

. Badged as a Rolls-Royce, the 30 hp was produced during 1905 and 1906 by Royce's company, Royce Ltd. at its factory in Cooke Street, Hulme,

Manchester Manchester () is a city and the metropolitan borough of Greater Manchester, England. It had an estimated population of in . Greater Manchester is the third-most populous metropolitan area in the United Kingdom, with a population of 2.92&nbs ...

. It was sold exclusively by Rolls' motor dealership, C.S.Rolls & Co., at a price of GBP 890. The engine was exhibited at the

Paris Salon The Salon (), or rarely Paris Salon (French: ''Salon de Paris'' ), beginning in 1667 was the official art exhibition of the in Paris. Between 1748 and 1890 it was arguably the greatest annual or biennial art event in the Western world. At the ...

in December 1904, along with the 10 hp, 15 hp and 20 hp models. Claude Johnson was keen that a

six-cylinder A straight-six engine (also referred to as an inline-six engine; abbreviated I6 or L6) is a piston engine with six cylinders arranged in a straight line along the crankshaft. A straight-six engine has perfect primary and secondary engine balanc ...

model was included in the Rolls-Royce line-up as other "quality" makers, especially Napier, were adding them to their ranges. The 30 hp was discontinued when the company changed to a single model policy and launched the 40/50 (Silver Ghost).

Engine

The engine is made of three separately-cast two-cylinder units with

monobloc head ''Monobloc'' refers to a component that is made in one block or casting. A monobloc engine or en bloc engine is an internal-combustion piston engine some of whose major components (such as cylinder head, cylinder block, or crankcase) are formed, u ...

s which are common with the

two-cylinder The engine configuration describes the fundamental operating principles by which internal combustion engines are categorized. Piston engines are often categorized by their cylinder layout, valves and camshafts. Wankel engines are often categoriz ...

10 hp and

four-cylinder The engine configuration describes the fundamental operating principles by which internal combustion engines are categorized. Piston engines are often categorized by their cylinder layout, valves and camshafts. Wankel engines are often categoriz ...

20 hp types sharing their bore of and stroke of . It is water-cooled and of 6,000 cc capacity with overhead inlet and side exhaust valves. A single Royce

carburettor A carburetor (also spelled carburettor or carburetter) is a device used by a gasoline internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the Vent ...

is fitted. Early cars have a high-tension ignition system using pre-charged accumulators, a

trembler Tremblers (''Cinclocerthia'') are a genus of perching birds in the family Mimidae that are endemic to the Lesser Antilles. They are medium-small, mostly brown or grey birds with long beaks and tails that typically are held cocked. Most recent au ...

and a coil ignition system; on later cars this is supplemented by a

magneto A magneto is an electrical generator that uses permanent magnets to produce periodic pulses of alternating current. Unlike a dynamo, a magneto does not contain a commutator to produce direct current. It is categorized as a form of alternator, ...

which could be used as an alternative. As the lighting supplied uses oil for the side and tail and

acetylene Acetylene (Chemical nomenclature, systematic name: ethyne) is a chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is u ...

for the headlights, there is no other drain on the accumulators, which need to be recharged between outings. The power output is at 1000 rpm.Rolls-Royce Motor Cars website
/ref> The engine speed is controlled by a governor that can be over-ridden by the pedal-controlled accelerator. A four-speed transmission carried over from the "Light" 20 hp model is connected to the engine via a short shaft. On this transmission, third gear is direct and fourth speed an overdrive ratio. A leather-faced

cone clutch A cone clutch serves the same purpose as a disk or plate clutch; however, instead of mating two spinning disks, the cone clutch uses two conical surfaces to transmit torque by friction. The cone clutch transfers a higher torque than plate or disk ...

is used.

Crankshaft

The

crankshaft A crankshaft is a mechanical component used in a reciprocating engine, piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating Shaft (mechanical engineering), shaft containing one or more crankpins, ...

is carried in seven

main bearing A main bearing is a bearing in a piston engine which holds the crankshaft in place and allows it to rotate within the engine block. The number of main bearings per engine varies between engines, often in accordance with the forces produced b ...

s in an attempt to keep vibration to a minimum, a problem on many early six-cylinder engines, as the dynamics of the layout were still not fully understood. Flywheels are fitted at both the front and rear of the crankshaft. After some early cars suffered broken crankshafts Royce modified the front flywheel to incorporate a

harmonic damper A harmonic damper is a device fitted to the free (accessory drive) end of the crankshaft of an internal combustion engine to counter Torsional vibration, torsional and resonance vibrations from the crankshaft. This device must be an interference ...

which overcame the problem.

Car

The car has a top speed of . There is a transmission brake operating on a drum fitted behind the gearbox operated by foot pedal and internal expanding drum brakes on the back axle operated by the handbrake lever. Suspension is by semi-elliptic leaf springs on both front and rear axles with an additional crossways helper spring on the rear. The axle is located by a triangular strut linking axle and chassis and the main drive thrust is transmitted to the car by links between the ends of the axle and forward spring brackets. By this means the springs are only responsible for suspension.

Artillery Artillery consists of ranged weapons that launch Ammunition, munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during sieges, and l ...

type wheels with wooden spokes were fitted. Two chassis lengths were made, the short is in length and the long . The track is the same on both lengths at . Rolls-Royce did not provide the coachwork. Instead, the cars were sold in chassis form for the customer to arrange their own body supplier. Both closed and open cars were made. Of the 37 or possibly 38 cars made, three were exported to the US, one to Canada and one to Germany. Only one car, a short wheelbase model with chassis number 26355 is known to survive.

References

* * * * {{Rolls-Royce 30 hp Cars introduced in 1905 1900s cars Brass Era vehicles Cars discontinued in 1906