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 effect of standardising 33 x 5' tyres on the gear ratio and performance of the 20 HP car.
| Identifier | ExFiles\Box 58\1\ Scan029 | |
| Date | 17th June 1927 | |
| COPY. X5820 X4565 To. Hs.{Lord Ernest Hives - Chair} from BJ. BJ7/E17.6.27. Standardisation Sheet. X.5820 X.4565 33 X 5" tyres 20 HP. At present I am not quite clear as to what difference these tyres will make to the gear ratio of a car. At present the gear ratio is already rather too high on closed cars. The majority of our cars are closed. WWill you kindly explain the matter to me as clearly as possible, as anything which will make the 20 HP. more sluggish in pick-up and on hills is a very great detriment. BJ. | ||