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).
Modifying an exhaust system to reduce spitting and booming noises.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan143 | |
| Date | 12th November 1929 | |
| (2) Hs{Lord Ernest Hives - Chair}/AJL1/BE12.11.29. Spitting noises are not improved by using this front expansion chamber. To improve it we suggest trying a cast aluminium rear end piece in place of the sheetmetal one instructed, and in addition, a down pipe having the same diameter as standard in order to retain the improvement in booming given by the shorter and smaller diameter intermediate pipe, which goes with the rear silencer. The system has not yet been tested for comparative power loss. We are doubtful whether the front expansion box and silencer front end will with-stand the great heat registered under dynamometer conditions. Hs{Lord Ernest Hives - Chair}/AJL. | ||