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).
Redesign, performance testing, and tyre development challenges of a prototype vehicle before the outbreak of war.
Identifier | ExFiles\Box 160\5\ scan0323 | |
Date | 8th July 1941 | |
Em.5/ET.8.7.41 - 3 - These results were just what we wanted technically, but we were not satisfied with the appearance of the car, and also it was a two-door saloon, with rather cramped luggage space and rear passenger accommodation. Monsieur Paulin, therefore, set to work to re-design the appearance and convert the body into a commodious four-door saloon, with plenty of luggage room. The result of his efforts was what the Company's engineers considered to be a very good looking motor car, and a wind tunnel model was made. The drag tests were most encouraging since, in spite of the increased body dimensions, the wind resistance figure was exceedingly low. A full size car was built and confirmed the wind tunnel tests. Since it had been decided to put the car on the market as a definite model, no liberties could be taken with the power plant at all. Nevertheless the car in full touring trim, with a driver and passenger lapped Brooklands at 109 1/4 miles per hour. The car was then taken to France, where every new Rolls-Royce chassis is subjected to a run of at least 15,000 miles of high speed continental motoring. As this car was intended to be especially suitable for the new motor roads, a considerable amount of this run was carried out on the Autobahnen and Autostrada. The major problem which immediately presented itself was that of tyre life. It was almost impossible to get a standard tyre to last more than a few miles if the car was driven flat out. Another disconcerting result was that, if one indulged in a short spurt of speed and then came back to 90 M.P.H., the tyre never got over its high speed treatment and, if these speed spurts were repeated, it was found that the tyre burst after exactly the same number of miles as would have been the case if the same distance had been covered continuously. With the assistance of the tyre Companies, we at once started to do the necessary development work to get a tyre to suit these extreme conditions, and were well on the way to success at the outbreak of war. Unfortunately, even our experienced test drivers took some time to get accustomed to the very high maximum speeds, and the first "Corniche" was completely smashed up just before the war started. This was the only car in existence, and it will therefore be some time after the war is finished before anyone can once again handle one of these rather surprising vehicles. It seems improbable that there will be any basic difficulty in accustoming the average Bentley driver to speeds between 100 and 110 | ||