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).
Speed and acceleration tests conducted on three cars at Brooklands.
| Identifier | ExFiles\Box 29\3\ Scan324 | |
| Date | 23th June 1931 | |
| To R.{Sir Henry Royce} From Ha/Rm.{William Robotham - Chief Engineer} c. to SG.{Arthur F. Sidgreaves - MD} Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} Ba. c. to Hy.{Tom Haldenby - Plant Engineer} PH. 8788. Ha/Rm.{William Robotham - Chief Engineer}1/RT. 23.6.31. 8788. 85771. BROOKLANDS TESTS. 19.6.31. Tests were conducted on three cars to estimate the acceleration and maximum speed obtainable by various power outputs, and the relative roughness engendered thereby. The cars were. (1) Std. Trials Car. G.S.R.14. (2) 16.G.IV. Japan engine with 110° shaft and Larger R.R. single carb. Free exhaust system. (3) 18.G.IV. Japan engine with 112° shaft and Twin Zenith carb. P.II. short type silencer and fishtail. The various power outputs are shewn on sheets I, II,A & III. Briefly it was expected that 18.G.IV would shew a considerable increase in acceleration between 20 & 50 M.P.H. over both cars and that 16.G.IV. would also shew a better performance than standard and a better maximum speed but would not be so fast as 18.G.IV. SPEED TESTS. The speed results obtained were :- CAR | Car wts. | Lap. Speed. C.O. closed. | Lap. speed. C.O. Open. | 1/4 mile. C.O. closed GSR.14 std. China. | 33.7 cwts. | 63.2 | - | 62.5 16.G.IV. Japan. Free Ex. system. | 31.8 cwts. | 64.8 | 69.66 | - 18.G.IV. Japan. Twin Zenith. P.II. Ex. System. | 35.6 cwts. | 68.7 | 70.64 | 67.67 18.G.IV. China. std. 25HP. Ex. syst. | 35.6 cwts. | 61.41 | - | - New Unit Increase Top spd. of this car. c.o. closed by 7.3 m.p.h | ||