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 to India Tyre & Rubber Co. Ltd. comparing the cornering power and measurements of Dunlop and India tyres.
| Identifier | ExFiles\Box 157\6\ scan0162 | |
| Date | 27th August 1937 | |
| 1336 August 27th 1937 Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls}10/AP. India Tyre & Rubber Co.Ltd., Inchinnan, SCOTLAND For the attention of Mr.P.Worth Dear Sirs, Replying to your letter of August 26th. The width measured on the arc of the silent variety of Dunlop 90 tyre, made specially for us, varies between 4½ and 4⅝ compared with the measurement of 5⅛ on the India tyre. maximum We are able to give you a few figures of the relative cornering power of various tyres, both your latest India and the silent Dunlop on 4" rims giving a figure of .39g. The old type of Dunlop 90 which had an extra rib each side of the main tread gave a figure of .465g. By putting a 6.50 India tyre on a 5" rim werwere able to increase the .39 to .45g. We are engaged at the moment in comparing the slip angles at various accelerations and should these prove of interest we will send them on to you. Yours faithfully, FOR ROLLS-ROYCE LTD. | ||