Rolls-Royce 30 hp
August 19th, 2008 | by rarzi |The Rolls-Royce 30 hp is an early car model produced by Rolls-Royce at their Manchester works and made in 1905 and 1906. The engine was exhibited at the 1904 Paris Motor Salon along with the 10hp, 15hp and 20hp cars. Claude Johnson was keen that a six cylinder 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).
The engine was made of three separately cast two cylinder unit which were common with the two cylinder 10 hp and four cylinder 20 hp types sharing their bore of 4?in (102?mm) and stroke of 5?in (127?mm). It is water-cooled and of 6000?cc capacity with overhead inlet and side exhaust valves. The crankshaft was carried in seven main bearings 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. Early cars had a high tension ignition system using pre-charged accumulators, a trembler and a coil ignition system; on later cars this was supplemented by a magneto which could be used as an alternative. As the lighting supplied uses oil for the side and tail and acetylene for the headlights, there is no other drain on the accumulators which need to be recharged between outings. The power output is 30?bhp (22?kW) at 1000 rpm.? The engine speed is controlled by a governor that can be over-ridden by the pedal controlled accelerator. A three speed gearbox was fitted at first, later changed to four speed, connected to the engine via a short shaft and a leather cone clutch is used. On the four speed type, third gear is direct and fourth speed an overdrive ratio.
The car has a top speed of 55?mph (89?km/h). 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. Artillery type wheels with wooden spokes were fitted.
Two chassis lengths were made, the short was 112?in (2845?mm) long and the long 118?in (2997?mm). the track was the same on both lengths at 56?in (1422?mm). 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.
The car in chassis only form cost ?890. Only one car, chassis number 26355 is known to survive.
| Manufacturer | Rolls-Royce Ltd |
|---|---|
| Production | 1905-1906 37 made[1] |
| Successor | 40/50 (Silver Ghost) |
| Engine(s) | 6000cc 6 cylinder. |
| Transmission(s) | three or four speed |
| Wheelbase | 112?in (2845?mm) or 118?in (2997?mm) |
| Length | 157?in (3988?mm) or 158.75?in (4032?mm) |
| Designer | Sir Henry Royce |
