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).
Extract from a visit to sales regarding a resonant exhaust note on the 20 HP model.
| Identifier | ExFiles\Box 48\4\ Scan217 | |
| Date | 14th July 1924 | |
| X.4238. Extract from DA {Bernard Day - Chassis Design} /EV {Ivan Evernden - coachwork} 4/M14.7.24. RE. VISIT TO SALES ON THE 10TH. INST. (6) 20 HP. EXHAUST NOTE X.4238. When running at 19 m.p.h. on top gear the exhaust system appears to be-come resonant over a very short range. This can be appreciated when driving in London, since one is usually driving round about this speed. Sales have had several complaints of booming which have been traced to this cause, and EV. {Ivan Evernden - coachwork} tried three cars, all of which had this feature. Would Hs. {Lord Ernest Hives - Chair} let us have his remarks. DA {Bernard Day - Chassis Design} /EV. {Ivan Evernden - coachwork} | ||