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).
'Goshawk' exhaust system on 20 HP cars, addressing noise levels and experiments with a silencer cut-out.
| Identifier | ExFiles\Box 48\4\ Scan181 | |
| Date | 27th November 1922 | |
| Sp.{Mr Spinney} from Hs.{Lord Ernest Hives - Chair} X.4238 Hsl/LG27.11.22. GOSHAWK EXHAUST. We do not anticipate being able to improve the Exhaust noise on the 20 HP. cars. We consider that the noise from the exhaust when judged from an open car, is remarkably silent. The only manner in which we can silence the exhaust still further, is to sacrifice power. We are, at the present time, experimenting with a silencer with a cut-out. it is possible, that if we fit a cut-out to the car, we might be prepared to sacrifice more power when it is closed. At present the cut-out is only experimental. We shall have to produce a large number of cars with the present exhaust arrangement. Hs.{Lord Ernest Hives - Chair} R.R. 199 (Sg{Arthur F. Sidgreaves - MD}01) (SD670 19-7-17) M/P18069 | ||