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 graph comparing Flywheel B.HP against Engine R.P.M. for a 'New Phantom' and a 'Bentley'.
| Identifier | WestWitteringFiles\N\2October1925-December1925\ Scan88 | |
| Date | 23th October 1925 guessed | |
| FLYWHEEL B.H.P. 140 130 120 110 100 90 80 70 60 50 40 30 20 300 ENGINE R.P.M. 1000 1500 2000 2500 3000 BENTLEY New PHANTOMCodename for PHANTOM I | ||