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).
The road performance of a concentric tube silencer fitted to car 103-MC.
| Identifier | ExFiles\Box 71\3\ scan0323 | |
| Date | 11th September 1925 | |
| R.R. 493A (50 H) (D.D. 31, 12-6-25) J.H.D. EXPERIMENTAL REPORT. Expl. No. REF Hs{Lord Ernest Hives - Chair}/AJL/LG11.9.25. CONCENTRIC TUBE SILENCER AS FITTED TO 103-MC. Road performance. The following figures give particulars of the cars' performance with cutout closed and open. Ticknall Hill Test. | | Starting speed. | Finishing speed. | Time taken. | |---------------|-----------------|------------------|-------------| | Cutout closed.| 10 m.p.h. | 53 m.p.h. | 68 secs. | | Cutout open. | 10 m.p.h. | 55.5 m.p.h. | 65 secs. | Acceleration on level road. | | Accelerating from :- 10 to 30 m.p.h. | 30 to 60 m.p.h. | | |------------------|--------------------------------------|-----------------|-------------| | Cutout closed | 10.3 secs. | 25.4 secs. | } time | | Cutout open. | 10 secs. | 22.15 secs. | } taken | It will be seen that the use of the cutout gives relatively little advantage under ordinary touring conditions. Above 60 m.p.h. the cutout open would prove a decided advantage. Hs{Lord Ernest Hives - Chair}/AJL. | ||