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).
Multiple road test trips, detailing routes, speeds, times, and general performance observations.
| Identifier | ExFiles\Box 69\4\ scan0015 | |
| Date | 1st February 1926 guessed | |
| F.Y. to Mr. Hives. NOTE on 8 trips between Derby (Friary Hotel) and Withington, via Ashbourne, Buxton, Cat & Fiddle, Macclesfield and Hazel Grove. Mean distance, 65 miles. Driver F.Y. Car 10 Ex. Time occupied Average speed Feb. 16. Derby to Withington............110 minutes...........35.45 m.p.h. " 17 Withington to Derby........110 do ............35.45 " 17 D.{John DeLooze - Company Secretary} to W..................120 do...............32.5 " 18 D.{John DeLooze - Company Secretary} to W...................95 do...............41.05 " 18 D.{John DeLooze - Company Secretary} to W..................100 do...............39.00 " 19 W. to D..................105 do...............37.14 " 19 D.{John DeLooze - Company Secretary} to W..................100 do...............39.00 " 20 W. to D...................95 do...............41.05 Mean speed for 520 miles..................37.58 Water temperature maintained generally at 100.C., with indicator of pressure guage showing zero to 4lbs. pressure. Rise in road from Withington to Cat & Fiddlee 1570 feet. Winds W. to S.W. Weather, Fair to Sleet storms. Top gear used throughout, except for two traffic checks in Macclesfield and Ashbourne. Feb. 20 Derby to London, via Loughboro', Melton, Oakham, Stamford and Welwyn. 148 miles Running time, 240 minutes. Stamford to Stevenage, 58 miles; time 73 minutes. Average speed for 148 miles...... 37.00 m.p.h. . do. . 58 do. ........47.69 do. General impressions. Remarkable consistency of performance under all conditions of road and weather. Suspension gave great stability in road-holding at high speeds. The steering was so light as to suggest the 20. h.p. car rather than the N.F. The chief difference observed between this car and the standard [text heavily crossed out] N.P. was the steering, the very rapid acceleration from 50 to 70 m.p.h, and the necessity for making use of the Ignition Control for optimum results. The highest speed recorded by the speedometer was 84 m.p.h. No incidents. | ||