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).
Performance losses due to different silencer configurations on a vehicle.
| Identifier | ExFiles\Box 18\3\ Scan346 | |
| Date | 10th August 1932 | |
| SILENCER LOSSES. 10.8.32. Tests 114° Camshaft. 5.25 c.r. 7" X 20" Tyres. R.R. Semi Expanding Carburetter. 22-EX. 11 X 41 Axle Brooklands Standard Silencer. Mean Lap Speed. MPH. Cut-Out Open Cut-out closed 87.53 81.64 Difference C.O. Open and Closed with Standard Silencer. 5.9 M.P.H. 19-EX. 12 X 41 Axle 6" X 19" Wheels Chateauroux Resonance Silencer. Mean 1/2 mile speed. Silencer removed. C.O. closed. 86.5 m.p.h. 84.5 m.p.h. Difference C.O. Open and Closed with Resonance Silencer. 2.0 M.P.H. | ||