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).
Request for detailed braking specifications of an 8-cylinder Isotta-Fraschini car for comparison purposes.
| Identifier | ExFiles\Box 30\6\ Scan133 | |
| Date | 8th November 1923 | |
| To HS.{Lord Ernest Hives - Chair} from DA.{Bernard Day - Chassis Design} X1559 DA{Bernard Day - Chassis Design}2/M8.11.23. RE. ISOTTA-FRASCHINI X.4609 X.1559 Referring to your Hs{Lord Ernest Hives - Chair}4/LG5.11.23., re the 8-cyl. Isotta, the figures you give for the braking will be very interesting to us and if they were reinforced by some more exact information about the Goshawk would enable us to make quite a useful comparison. Could you give us for instance the weight on the front and rear wheels, and the total weight of the particular 20 HP. quoted in these tests? We should also like to know the leverages on the Isotta brake gear in the form of the lengths of the levers without reference to the angle at which they work, that is to say, we should like the length of the operating lever from the pedal to the brake countershafts, the length of the lever on the countershaft itself, the dimensions of the cam, and the dimensions of the shoes. I do not suppose that it is possible to give us accurately the pressure exerted by the driver on the pedal. We have assumed this in our calculations to be 150 lbs. that is to say, roughly the weight of a man. It would be very useful information if we could obtain a more accurate idea of which this was. We think sometimes it may be more than 150 lbs. but we are merely guessing of course. The maximum on the hand lever would also be of interest. DA.{Bernard Day - Chassis Design} | ||