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).
Graph comparing the power at the road wheels (B.HP) against engine R.P.M. for the S.S. and Phantom models.
| Identifier | ExFiles\Box 17\7\ Scan040 | |
| Date | 22th August 1929 | |
| POWER AT ROAD WHEELS. S.S AND PHANTOM. 3RD GEAR B.H.P. AT ROAD WHEELS. AVERAGE PRODUCTION PHANTOM : -------- AVERAGE EXPTL S.S. : CUT OUT CLOSED ENGINE R.P.M. | ||