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).
Findings on suction noise, power reduction due to an inlet silencer, and gearbox noise levels.
| Identifier | ExFiles\Box 19\4\ Scan307 | |
| Date | 27th February 1931 | |
| - 2 - EP{G. Eric Platford - Chief Quality Engineer}8/H27.2.31. (5) Contd; The suction noise is certainly quieter, but the "snort" noise when suddenly opening up from closed throttle is more noticeable. (6) POWER. The dynamometer power at higher engine speeds is less than standard by 3 to 5 HP. (i.e. 4½ %) due to inlet silencer. We have not, however, been able to appreciate any less comparative performance on our road tests. (7) GEAR BOX NOISE. We do not consider the standard of gear noise is as quiet as that obtained with the standard Phantom II. EP.{G. Eric Platford - Chief Quality Engineer} | ||