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 test results for car 1.EX, a 4-seater open touring body, comparing high and low compression engine settings.
| Identifier | ExFiles\Box 29\3\ Scan098 | |
| Date | 9th August 1922 | |
| Particulars of car 1.EX - 4-seater open touring body - windscreen and hood - all accessories - weight complete 46 3/4 cwts. during tests. 14.X 52 axle ratio. Tests were taken to prove that ignition and mixture were set to give the best results. | TESTS. | High compression. 23 3/4 cu. ins. | | Low compression. 26 cu. ins. | | |---|---|---|---|---| | | Exhaust cut-out. Open. | closed. | Exhaust cut-out. Open. | closed. | | Max. speed for one lap. | m.p.h. 71.4 | m.p.h. 65.5 | m.p.h. 69.4 | m.p.h. 65.74 | | Max. speed for 1/2 mile. | m.p.h. 67.4 | m.p.h. 63.5 | m.p.h. 65.22 | m.p.h. 62.7 | | Acceleration. | secs. | secs. | secs. | secs. | | 10 m.p.h. to 65 m.p.h. | 37 1/4 | 50 | 47 | Impossible | | 20 " " 65 " " | 34 | 46 1/2 | 41 | to | | 30 " " 65 " " | 29 | 35 | 35 | get | | 40 " " 65 " " | 26 1/2 | 32 | 32 1/4 | | | 10 " " 60 " " | 30 | 37 | 34 | 42 1/2 secs. | | 20 " " 60 " " | 27 | 31 | 32 | 36 " | | 30 " " 60 " " | 21 | 25 | 28 | 32 " | | 40 " " 60 " " | 17 | 19. | 20 1/2 | 23 " | | 10 " " 50 " " | 21 | 23 1/2 | 23 | 25 " | | 20 " " 50 " " | 17 | 19 | 20 | 22 1/2 " | | 30 " " 50 " " | 12 | 14 | 15 | 17 " | | 40 " " 50 " " | 7 | 7 1/2 | 8 1/2 | 10 1/2 " | | 1/2 mile acceleration test. | | | | | | starting at 10 m.p.h. | 40 | 43 | 45 | 47 1/2 " | | 20 " " | 36 | 37 | 38 1/2 | 40 " | | 30 " " | 33 | 33 | 36 | 37 " | Hs.{Lord Ernest Hives - Chair} | ||