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 for E.R. Hall's Bentley showing MPH vs RPM for each gear, specifically geared for hill climbing.
| Identifier | ExFiles\Box 90a\3\ Scan063 | |
| Date | 16th May 1934 guessed | |
| E.R. HALL'S BENTLEY GEARED FOR HILL CLIMBING 5.50 x 18 DUNLOP BUTTRESS AXLE RATIO 9/46 = 5.11:1 ROAD WHEELS REVS/MILE 701.9 TABLE: R.P.M TOP | 60 MPH | 3,580 3RD | 60 MPH | 4,450 2ND | 30 MPH | 2,845 1ST | 30 MPH | 3,617 AXIS LABELS: M.P.H R.P.M GEAR LABELS: TOP 3RD 2ND 1ST F.D. | ||