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).
The speed and acceleration trials for Chassis No. 20 MY at Brooklands.
| Identifier | ExFiles\Box 155\1\ scan0069 | |
| Date | 3rd March 1933 | |
| X788 LE2/G/3.3.33. O.K. [stamped and crossed out] Copy to Mr. [illegible] Copy to [illegible] Copy to Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Re Chassis No. 20 MY. Trials. I took this car down to Brooklands and with two passengers and the cut-out open we lapped at 86.6 m.p.h., did the flying half mile at 90 m.p.h. and the mile at 88.6 m.p.h. The lap speed with the cut-out closed and three passengers was 82 m.p.h. The acceleration figures were as follows:- 10 to 30 m.p.h. ..... 8.6 seconds. 10 to 40 m.p.h. .....13.2 " 10 to 50 m.p.h. .....19.6 " 10 to 60 m.p.h. .....25.4 " 10 to 70 m.p.h. .....35.00 " These figures are with two passengers and the cut-out open. I hope to get 8 MY., Harris, ready for test next week and I will make some further tests of acceleration. It is extremely difficult to get true acceleration time as one starts to climb by Vickers' Sheds when high speeds are attained and this naturally does not give one a true reading. Acceleration using the gears and changing from 2nd to 3rd gear at 40 m.p.h. and 3rd to top at 70 m.p.h., with two passengers and the cut-out open, one gets to 60 m.p.h. in 14.6 seconds and 80 m.p.h. in 31 seconds. It may interest you to know that the speedometer's maximum reading was 95 m.p.h. on the lap, and the minimum was 85 m.p.h. [Signature] J.E.R./3/33 | ||