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).
Manifold design, carburetter placement, and comparative temperature readings for engine performance.
| Identifier | ExFiles\Box 50\3\ Scan078 | |
| Date | 26th May 1921 guessed | |
| Oy9 - G 24521 Sheet #2. We wish to suggest that a similar experiment should be carried out with our own manifold. Pockets should be provided at each inlet bend and the fuel collected and examined. Also, that if the carburetter could be moved to the left hand side of the engine, it would be quite possible to use the type of combined manifold shown in figure 4 of Mr. Dorris' paper, which he says gives such satisfactory results. It will be noticed on this manifold that the bend above the carburetter is literally exhaust-jacketed, but that the rest of the manifold is not heated except by conduction from the exhaust ports - a kerosene boiler being provided to dispose of the heavy ends which accumulate in starting and slow running. The temperatures mentioned by Mr. Dorris are also interesting. He states that in manifold No. 2 a temperature of 225° F. {Mr Friese} was obtained, which was too high for good power, but that with the new manifold, figure 4, a temperature of 175° F. {Mr Friese} is obtained, which is satisfactory. On our present heated manifold we obtain a temperature of 120° at the Tee piece with the water temperature at 175° and the engine running light, and 118° with the water temperature at 170° and engine on full throttle. 49°C 50°C When this manifold is arranged to take the blast from Nos. 1 and 6 cylinders only, we get 145° when running light and 120° at full throttle with the same engine temperature. One would rather therefore that it is possible for us to increase the heat a little more without danger of serious loss of power or pre-ignition. Yours truly, ROLLS-ROYCE OF AMERICA, Inc. Per M. {Mr Moon / Mr Moore} Olley MO/G CC Mr. Nadin Mr. Bagnall Mr. Hulley Mr. Southern Mr. Caswell | ||