From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Engine components including big end bearings, carburettors, blowers, superchargers, and engine speed limitations.
| Identifier | ExFiles\Box 173\3\ img082 | |
| Date | 4th April 1934 | |
| -3- BIG END BEARINGS. Interesting in that the sideways location is on the steel rod instead of white metal. This gives a greater effective big end length, stronger rod and a much cheaper construction. CARBURETTOR WITH CENT. BLOWER. Graham Paige have found it desirable to use a plain choke carburettor with the blower. They state that at low speeds the blower is highly sensitive to any depression on the suction side, and also the depression is not needed with a blower for snap opening up. They tried an expanding constant-depression type of carburettor but found they lost their boost from 1000 to 1500 R.P.M. Another advantage of the fixed choke carburettor is that it tends to reduce boost where too much is not wanted; i.e., at maximum speed. STARTING, WARMING UP, SNAP ACCELERATION, SLOW RUNNING. They claim that the centrifugal blower has improved all these features. Certainly the finished car behaves in a refined manner. They have eliminated the exhaust heated hot spot, the only heat now used being a water jacket round the blower. PETROL BUILDING UP IN BLOWER. They have an ingenious scheme for preventing petrol building up in the blower. They also have a continuous downward slope from the carburettor to the intake ports to ensure that any liquid fuel is drained away. CONSTRUCTION OF SUPERCHARGER. The rotor is a simple, unmachined casting. There is no spring drive in the system except the couplings. There is no slipping clutch. It is understood that in production quantities of about 1000, unit will cost about 25/-. LIMITATION OF ENGINE SPEED. As previously mentioned, this is arranged by allowing the valves to bounce at 5000 R.P.M. The power falls off before then due to the fixed choke carburettor. Do not recommend restriction by reducing valve or induction pipe sizes. | ||