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).
Phantom III chassis power curve, gear ratios, and clarification on superchargers.
| Identifier | ExFiles\Box 146\1\ scan0098 | |
| Date | 13th November 1937 | |
| W/P. To Sr. from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} 1240- Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}1/AP.13.11.37. PHANTOM III. CHASSIS. In reply to your memo. Sr/DN.10/MLG.9.11.37. regarding the information required for a customer on the above chassis, we enclose a power curve of the unit giving figures of open exhaust and with exhaust system fitted. Regarding your request for a power curve with "compresseur" the answer is that we do not fit a "compresseur" by which we assume your mean "supercharger" or booster The gear ratios of engine/prop shaft are as follows. Top gear - direct. 4.25 3rd. gear - 1.31 : 1 5.57 2nd. " - 1.98 : 1 8.42 1st. " - 2.95 : 1 12.53 The axle ratio is 8/34. at 4500 R.P.M. the corresponding road speed is 95 m.p.h. in top gear. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||