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).
Test data table for rear dampers, measuring time for 360-degree rotation at various speeds on two different road surfaces.
| Identifier | ExFiles\Box 16\5\ Scan038 | |
| Date | 25th November 1931 guessed | |
| Time in secs. to complete 360° of the O.S. rear damper in an upward direction Specification of rear dampers. | Speed in MPH. | ROAD SURFACE "A" | ROAD SURFACE "B" Outward direction | Inward directn. | Outward directn. | Inward direction. Damper loads 80/85. 10 | 180 | 192 | 1188 | 20 | 46.4 | 59 | 112.6 | 120.6 30 | 29.6 | 46 | 54.6 | 91.3 40 | 12.5 | 15.2 | 27.8 | 45 50 | 9 | 11.6 | 25 | 27 60 | | | 11.6 | 24 70 | | | 11 | 16.6 Damper loads 80/85 with .055 dia. hole in H.P. valves. 10 | 188.5 | 190.4 | 456 | 490 20 | 37 | 55 | 74 | 94 30 | 22 | 25.2 | 41 | 71.6 40 | 14 | 16.8 | 22.2 | 37.2 50 | 9.2 | 10 | 17.2 | 27 60 | | | 13 | 19.5 70 | | | 12 | 12 Damper loads 90/115 No holes in valves. 10 | 368 | 384 | | 1211 20 | 50 | 66 | 125.4 | 146 30 | 38 | 43 | 60 | 63.3 40 | 15 | 19 | 40.5 | 45.4 50 | 10.5 | 10.5 | 18.2 | 29.4 60 | | | 14.5 | 22 70 | | | 12 | 14.8 Road surface "A" = Canal Rd. (Sinfin Lane) " " "B" = Road on to Six Hills. | ||