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).
Comparing shutters and louvres, discussing radiator performance, and proposals for coachwork ventilation.
| Identifier | ExFiles\Box 19\3\ Scan343 | |
| Date | 12th May 1930 | |
| Oyl/DM.{D. Munro}12.5.30 -3- Since this type of shutter closes flush they are practically invisible in normal use. They close on rubber buffers and consequently do not squeak or rattle. We regard them as much better than louvres because they hold the warm air in in winter and do not therefore have to be supplemented by blanking plates of asbestos-board, such as have to be used in any car with louvres in the U.S. in winter. Also in normal operation of the car they do not cause increased engine noise as louvres do. As compared with the sliding shutter, they do not stick, do not damage the paint when used, and occupy less space on the bonnet side. They must also have some extracting effect like louvres. Radiator. Thorne Donnelley's report of last summer which you have probably seen, referred to an American P.I with automatic shutter set at 160ºF and with a considerably smaller radiator than P.II. He was operating in deep gravel at air temperatures of 120ºF and up, with extremely dry air and considerable altitude, and though he lost water, the loss was slight compared with cars of other makes. At the same time it is fair to state that on long up-grades in Californian mountains, summer temperatures and high altitudes, the loss of water is more rapid than we should like. I would like to suggest that the American Cartridge Co's hexagonal tube copper matrix (which we have used for years) may be more efficient than the present round brass-tube matrix on P.II, and is at least worth careful examination. Coachwork. From the coachwork viewpoint we should like to retain a plain non-ventilated bonnet if in any way possible. The reason concerns the ventilation of the scuttle and front compartment. The best way of doing this is undoubtedly by large side ventilators facing forwards, because - cont'd.{John DeLooze - Company Secretary} | ||