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).
Road tests from France discussing weather impact, fan noise, and fuel system performance.
| Identifier | ExFiles\Box 5a\2\ 02-page120 | |
| Date | 27th June 1929 | |
| 4794G To H.R. From G.W.H. Hôtel de France, Châteauroux, Indre. 27/6/29 We have received your letter of the 25th. We sent you yesterday our report on the tests carried out at Clermont-Ferrand. We do not think any further tests in that district would be of any value, as weather conditions have completely changed. It is quite cool, the temperature having dropped to 17°C. On the road, it is down to 8°C, in fact during the morning it is as low as 3°C. As reported during our daily runs in very hot weather and practically no wind we have had no signs of over-heating. We are quite aware that the results you have obtained by pushing the fan closer to the radiator is beneficial, it was objected to on account of the noise. We are with this car getting more noise from the fan than what we would really care for. If however during the next 2 or 3 days we are here the condition of the weather changes, we will carry out your suggestions and note the effect. Mr. Northey reported to me that on his run down here the temperature of the water on his car actually rose when he opened the rear shutters of the bonnet; no solution could be offered for this. We will attend to the Bijurs supplying the rear and front shock damper connecting links and the steering arm. We shall by the time you receive this letter have finished the mileage here and the car will be leaving for Grenoble either Monday or Tuesday. Re the S.S. that Mr. Northey brought down here, we tested the flow of petrol through the tap and all the carburetter. Ample petrol was passing for the requirements of the engine at high speeds. In regard to the boiling of the petrol, we had no time to verify this, also as the filter is fitted on the opposite side to what it used to be on the Phantom, we dismissed the temperature effect being the cause. The most obvious thing was the baffle fitted to the carburetter for silencing the exhaust of the air pump. We are aware that this baffle is considerably more than the one that was fitted to 18-EX. The baffle on 23-EX was similar to the one that is fitted to 21-EX, and we were alive to this fact during our last tests here. We did not observe any failure of the petrol supply on 23-EX, but it does not prove that this trouble cannot arise, and that the efficiency of the pump is decreased by it. We disconnected the baffle on 21-EX and asked Hyman to note the results. If it was O.K. under these conditions, to reconnect it up and try again. If it again failed, to | ||