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 Chassis No. 22 G.V. at Brooklands, detailing lap times, acceleration data, and engine notes under windy conditions.
| Identifier | ExFiles\Box 155\1\ scan0195 | |
| Date | 31th March 1936 | |
| GRY{Shadwell Grylls} (handwritten) CHASSIS NO. 22 G.V. Performance Tests on Brooklands. Strong headwind on Railway Straight. Following wind comming off Byfleet Banking. Results seriously affected by this. Two laps at full throttle, max. ignition advance were timed at:- 2 mins. 18.3/5 secs. 71.9 m.p.h. 2 " 18.1/5 " 72.1 m.p.h. Two laps at full throttle, ignition retarded 5 notches were timed at:- 2 mins. 20.3/5 secs. 70.8 m.p.h. 2 " 18.4/5 " 71.8 m.p.h. A further lap with ignition retarded 4mmnotches was timed at:- 2 mins. 18.3/5 secs. 71.9 m.p.h. ACCELERATION FROM 10 m.p.h. SECS. TO 20 m.p.h. 4.1 30 " 13.7 40 " 14.3 50 " 18.8 60 " 25.7 {50.0} 70 " {38.5} ACCELERATION FROM 20 m.p.h. SECS. {4.4} {4.6} 10.3 16.2 23.9 35.0 ACCELERATION SECS. 30 m.p.h.- 40 m.p.h. 4.6. 40 " - 50 " 4.9. 50 " - 60 " 6.6. {22.3.} 60 " - 70 " {10.3.} 1/4 mile standing start. {24.0 secs. 23.7 "} 1/2 mile flying start {25.6 secs. 25.0 "} Mean speed. 70.4 m.p.h. 72.0 m.p.h. (These were directly against wind) NOTE. No trouble was experienced in starting engine after a quarter of an hours stop after any of the runs. Throughout these tests particular attention was paid to the possible formation of vapour locks in the petrol system. The performance was quite consistent, lap speeds were maintained practically constant; several slow runs were then included, and on opening up, normal full throttle condition was at once attained on every occasion without hesitation. Carburation was satisfactory throughout the acceleration tests. It can be said that the petrol supply was regular and adequate. | ||