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).
Acceleration tests, including speedometer accuracy and performance timings.
| Identifier | ExFiles\Box 5a\4\ 04-page081 | |
| Date | 30th July 1928 | |
| x5840 Rm{William Robotham - Chief Engineer} 30th July 1928. 21 G IV. ACCELERATION TESTS. AXLE RATIO. 11. x 50 DUNLOP "90" TYRES: 6 x 19 3,000 Revs. at 60 M.P.H. SPEEDOMETER READING. CORRECT READING. SECONDS. for speedometer reading over half mile. 34 30 68.8 45 40 51.- 55 50 41.5 68 60 34.5 speedometer varies 81 70 29.5 from 13 - 16% fast. 80 25.6 CORRECT SPEED. 10 - 20 5.0 secs 10 - 30 10.1 10 - 40 15.35 10 - 50 24.9 10 - 60 35.3 ----------------------- O.W.H. | ||