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).
Summary of comparative tests on engine cooling, comparing ventilated bonnets against Hispano-Suiza and American cars.
| Identifier | ExFiles\Box 24\5\ Scan292 | |
| Date | 22th July 1930 | |
| SUMMARY. Our comparative tests have proved that, with a ventilated bonnet, we are at least as well cooled as the best car we know of, the HISPANO SUIZA, and considerably better cooled than the average American car. The trouble is that most of our cars have shutters not ouvres fitted, and most of our customers are too lazy to use these shutters in the bonnet. If the Americans can get away with the scanty undershields they use in a country where the conditions are in places of a colonial nature, we ought to be able to do something to improve matters in this direction, since we clearly cannot sacrifice the silence obtained by the plain bonnet. However, it will be seen that even in our standard condition with the new fan belt and bonnet shutters closed we are better cooled than the American cars we have tried so far. The HISPANO fit neither radiator thermometer nor warning lamp. If 24-EX, now running in France had been so equipped there would have been no indication whatever that the car was on the point of overheating since the 5 pints of water lost were insufficient to affect the cooling system, and it has since been proved that they were ejected by splashing. A general impression of the American cars is that they are able to make very good engines, their principle attribute being smoothness with a good performance. Judging | ||