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).
Overheating potential of the 20 HP model compared to the 40/50 HP model.
| Identifier | ExFiles\Box 24\4\ Scan188 | |
| Date | 22th August 1924 | |
| PN{Mr Northey}2/DN22.8.24. -2- Although By.{R.W. Bailey - Chief Engineer} is correct in stating that the system of cooling on the 20 HP is more efficient, having regard to the available surface for cooling compared with the engine dimensions, at the same time in practice, there is no available advantage, because the 20 HP has so small a margin of power, and consequently when touring, the throttle is open an altogether larger proportion of the time than in the case of the 40/50 HP model. My impression is that the 20 HP under stressful conditions, will be found to overheat at least as much as does the 40/50 HP. On the occasion when H.{Arthur M. Hanbury - Head Complaints} and I drove the Beatonson car from West WitteringHenry Royce's home town to London, with a certain amount of South-West wind behind us, the water was practically on the boil nearly all the time, and in fact at Ripley, I actually put in some water. This may not have been necessary, but it arose, as it would with the ordinary owner, from the fact that one felt quite ignorant as to the amount of water which might have been lost and therefore a certain amount of anxiety existed as to contingent harm being done. As we could not, of course contemplate turning out the E.A.C. having so harmful a point for criticism in respect of over-heating, as is the case with the 40/50 HP model, I suggest that it is of great importance a test be immediately made whilst the summer temperatures last, with the latest type of E.A.C. chassis, such as I tested on Wednesday last at Derby, in the South of France, preferably the hills taken being those recently covered by me, i.e., Col du Lautaret and the Col du Galibier, and that the Hispano should also be taken on this test in order that comparative tests can be made, under similar conditions, of a car which it is known is altogether better than our own car in respect of over-heating. (Sgd.) P.N. | ||