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 Leyland Motors regarding gearbox tests, gear ratios, and a clutch drawing.
| Identifier | ExFiles\Box 140\3\ scan0150 | |
| Date | 21th March 1938 | |
| 1175 March 21st.1938 Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls}3/AP. V.W.Pilkington Esq., Messrs Leyland Motors Ltd., LEYLAND, Lancs. Dear Mr.Pilkington, Robotham has handed to me your letter about the R.R. gearbox tests. As regards altering the ratios, the over-drive arrangement which you saw at Derby will not go into the casting you have at Leyland, owing to the fact that we had to spread the shaft centres to obtain the required gear ratios. The ratios we use on the over-drive are .83, 1.0, 1.45 and 2.7. It does not look as if these would suit your purpose any better than the ratios you have, and in addition we have not for some time got a casting available for the overdrive ratios. Robotham has suggested that we might make for you a special pair of 3rd. speed gears of whatever ratio you want, if this will help you with your tests. Perhaps, therefore, you would let us know whether you would like us to do this. They would take some time to make unless you accept un-ground gears because the tackle we have at the Works is only suitable for normal and overdrive ratios. From the drawing of the clutch you have sent us you certainly are giving the synchro-mesh cones a job of work. Yours sincerely, | ||