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).
Proposed modifications to improve smoothness and reduce noise on the 20/25 HP test car.
| Identifier | ExFiles\Box 5a\4\ 04-page011 | |
| Date | 26th January 1934 | |
| W/S. X5840 To Ex. from E/Lid.{A. J. Lidsey} E/Lid.{A. J. Lidsey}3/HP.26.1.34. c. CE. c. WGT. c. Hs.{Lord Ernest Hives - Chair} c. By.{R.W. Bailey - Chief Engineer} c. 20/25 HP. Next 10,000 miles test car. --------------------------------------- Cx.{Major Len W. Cox - Advertising Manager}1/KW.25.1.34. ---------------- The question of smoothness and silence is one which is always to the fore when modifications to design are under consideration. The mounting of the engine is, in the light of present knowledge, the point where the greatest improvement as regards silkiness or smoothness can be affected. As long as we retain the unit construction of engine and gear box it is not possible on the 20/25 HP. car to achieve any real change in this direction. On the next 10,000 miles 20/25 HP. car following the one under present consideration it is hoped to incorporate amongst other features a separate gear box which will permit of major changes in the engine suspension. In the meantime a more careful study of the items given in E/Lid.{A. J. Lidsey}1/HP.S.1.34 will show that seven out of the 35, or 20% have for their object reduction of noise and fuss. Improvements in this direction have, therefore, not been neglected so much as Cx.{Major Len W. Cox - Advertising Manager}1/KW.25.1.34 might suggest. Items (8) (9) and (10) have for their sole object improvements in engine gear noise, which is one of the major sources of noise at present. Item (17) Flexible silencer mounting, will allow the exhaust system to flex as a whole with the engine unit. At present the exhaust system restricts the free movement of the engine in its mounting and has been proved to be a contributory factor to low speed roughness, and to exhaust booms generally. Item (18) modifications to cure 'crackles' and 'rattles' is to reduce contraction noises in the exhaust system | ||