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).
Comparing the performance of silent gearboxes from several competitor cars.
| Identifier | ExFiles\Box 179\2\ img087 | |
| Date | 22th December 1931 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} c. SG.{Arthur F. Sidgreaves - MD} for. c. F.{Mr Friese} Da.{Bernard Day - Chassis Design} c. By.{R.W. Bailey - Chief Engineer} ORIGINAL Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}6/KT.22.12.31. K2061. SILENT GEARBOXES. We have just had an opportunity to test several cars with a constant mesh indirect gear. The cars tried were, Buick 3 speed, MG. 4 speed, Panhard 4 speed, Packard 4 speed, Nash 3 speed and Auburn 3 speed. The Panhard was unusual in that it had 4 forward silent helical gears. The idling on this car was not good, but 3rd. gear was fairly quiet. All the others apart from the MG. were very quiet idling irrespective of whether the 3rd. or 2nd. gear under load was quiet or not. This was most noticeable on the Buick and Packard on which no attempt had been made to silence the gear below top, these gears being very noisy. The idling on these relatively cheap cars was better than the average of our synchromesh boxes and in fact as good as our best. The Nash and the Auburn had quiet 2nd. helical gears and synchromesh. The Nash 2nd. gear had a distinct whine on the overrun and was slightly quieter than the box on 20.G.IV. The Auburn 2nd. gear was very free from whine, the gear noise being of the type made by the Chrysler spool gear, but not as good as the Chrysler. This box was, however, quieter than anything we have yet produced. This box is quite a conventional American box with a hollow side shaft running on plain bearings on a stationary shaft, the 2nd. speed helical gears being in the middle of the box. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||