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).
Technical letter discussing overheating issues, brake linings, and requesting cooling system temperature data.
| Identifier | ExFiles\Box 14\7\ Scan044 | |
| Date | 9th July 1930 | |
| -3- We should like you to make sure that the ignition setting is the best for the cool running of the car. We presume that during your trouble with the valve taking up its clearance the car was never run with this valve actually off its seat, as of course this would almost certainly cause over-heating. We note that you do not like the 'Mintex' brake lining. We will send you some standard brake linings out also an autovac with a larger drop valve to ensure that your petrol supply is adequate at all speeds. We note your observations re the valve springs that are available in France. We should like you to let us have one back as a model. We should like to know whether you can detect any difference in the temperature at which the car runs with the best petrol and the worst petrol you can get hold of. One other fact in connection with the cooling system we are interested in is whether the top water temperature does consistently follow the atmosphere. If the top water temperature was 80°C. when the atmospheric temperature was 20°C, we should expect the top water temperature to be 90°C. when the air temperature was 30°C. We believe, however, though the cooling system must follow this law, the heat output to the cooling system increases rapidly as the air temperature rises, and so the proportionality (both way) does not hold. If you could get figures for the top water temperatures against atmosphere over a given road-way, taking readings at various | ||