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).
Technical note comparing water pump specifications for Phantom, Spectre, and 25-HP engine models.
| Identifier | ExFiles\Box 149a\1\ scan0050 | |
| Date | 28th September 1934 | |
| Rm{William Robotham - Chief Engineer} x4694 339 To Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} from E/JNR.{Charles L. Jenner} E/JNR.{Charles L. Jenner}1/HP.28.9.34. Water Pumps. Engine | Rotor Dia. | Pump Speed at 3500 Engine RPM. | Tip Speed ft. per sec. --- | --- | --- | --- Phantom. | 3" | 5250 | 68.7. SpectreCodename for Phantom III | 4" | 3500 | 61 25-HP | 3" | 5250 | 68.7. E/JNR.{Charles L. Jenner} | ||