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).
The aerodynamic development and evolution of the Corniche Bentley.
| Identifier | ExFiles\Box 160\5\ scan0321 | |
| Date | 8th July 1941 | |
| THE EVOLUTION OF THE CORNICHE BENTLEY ----------------------------- In 1931, when Rolls-Royce first took over the Bentley Company, some wind tunnel tests were made on the first 3½ litre Saloon car. Results were illuminating, but not very helpful towards improving the top speed of a motor car which must suit the average Bentley customer. Briefly, it was found that small excrescences such as lamps, horns or mascots on the front of a car have little of no effect on its speed. Making drastic alterations to the front as a whole, however, cut down the drag considerably. The best shape appeared to be something on the lines of the Lancia, a sketch of which is attached. The main point about this is that there are no sharp edges and the gap between the wings and the body is filled in. Unfortunately, in 1931, we particularly wished to retain the original Bentley appearance, and therefore any sweeping alterations to the radiator were out of the question. We found that, unless we altered the front, nothing we could do at the back made very much difference. With the altered front, however, a measurable improvement was obtained by a sweeping back and tail. When we had combined all the improvements (which produced an entirely unconventional looking car), we got a figure of merit for this and then turned a model of the standard saloon back to front in the wind tunnel. We were somewhat disgusted to find that, with this arrangement, a lower drag figure was produced than with our streamlined vehicle. Nothing further was done, therefore, to reduce the wind resistance of the car sold to the public, until just before the war. As soon as the Germans began to build their motor roads, it became evident that a vehicle designed for the winding lanes and congested main roads of Britain would have to be modified if it was to take advantage of this new road engineering. Before we started to design a car suitable for the Autobahnen, therefore, we looked round to see if we could get any full scale results which would be of value from cars that had already been built for private customers. We found that an enthusiast, Monsieur Embiricos, had, with the assistance of a French Engineer, Monsieur Paulin, produced quite a practical streamlined Bentley which seemed to be considerably faster than the standard product. In doing this he had taken liberties with the radiator, as will be seen from the attached picture, and this in no way resembled the standard Bentley. However, the "tout ensemble" was not altogether unpleasant. | ||