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).
Letter responding to Major Cox, discussing car performance, engine vibration, and braking systems.
| Identifier | ExFiles\Box 19\1\ Scan132 | |
| Date | 26th October 1931 | |
| COPY. Cx{Major Len W. Cox - Advertising Manager}4/ES261031 30,Curzon Street, W.1. Dear Major Cox, I have to thank you for your letter of the 26th instant. As explained to your firm in the first place, owing to the present depression I have unfortunately no intention of purchasing one of your new models at present - especially as the secondhand market offers such excellent value in your cars. However one cannot foretell how soon things may improve. Meanwhile, I was greatly interested by your Continental model, indeed, my interest in motor cars generally and especially of the sporting class, is such that I cannot resist the temptation of replying to your inference that the vibration felt with this engine is inseparable from a high-power higher power output. With this I do not agree at all - in fact I find that most of the engines with the greatest records for high efficiency and reliability are conspicuously free from vibration- e.g. Alfa Romeo, Talbot 105, etc. My 1750 c.c. supercharged Alfa Romeo engine develops more than double the B.H.P. for c.c. than does the Phantom engine, yet it runs with glassy smoothness under full load from 1000 to 5000 R.P.M., as I would be pleased to demonstrate to you any day. It seems to be merely a question of rigidity of crankshaft, of its location relative to the cylinder head ( vide the direct bolting from cylinder head to main bearings on the 4900 c.c. Bugatti which is so successful) and of suitable engine mounting in the frame to prevent the frame "wriggling" under torque reaction. Naturally the higher the power output, the greater the difficulty in securing perfect smoothness. With regard to the brakes, I find, apparently in common with all the makers of well known racing cars, that front wheel skids are a theoratical bogey, and that a far stronger braking effect, coupled with far greater immunity from skidding, is obtained when a slightly greater load is taken on the front wheels. I made extensive tests some time ago on a Bentley that had independently adjustable brakes. (contd- | ||