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 data comparison for two engine units, including acceleration figures and maximum speeds.
| Identifier | ExFiles\Box 124\2\ scan0167 | |
| Date | 14th May 1940 | |
| -2- Rm{William Robotham - Chief Engineer}/TAS.{T. Allan Swinden}6/JMe.14.5.40. (cont'd) 11 B.V. Engine unit B.80 No.3 11/41 axle. .836 overdrive ratio. Wt. of car 2 up with full tank 4520 lbs. Frontal area 25.6 sq. ft. Wind resistance coefficient K = .0017 6.50 x 16 tyres give 734 wheel revs/mile. and 2740 Engine revs/mile. 4 B.50. B.80 No. 1 9/37 axle. .836 overdrive. Wt. of car 2 up with full tank 4850 lbs. Frontal area 27.2 sq. ft. K = .0017. 7 x 16 tyres (as fitted) give 702 wheel revs/mile and 2610 Engine revs/mile. 6.50 x 16 tyres give 734 wheel revs/mile and 3020 Engine revs/mile. 11.B.5. 4.B.50. A.{Mr Adams} B. C. D.{John DeLooze - Company Secretary} E.{Mr Elliott - Chief Engineer} F.{Mr Friese} Acceleration Calculated. Actual Calculated Actual figures. All figures with dual carb. M.P.H. 3.S.U. Carbs. Dual Carbs Dual Carb 6.50x16 7x16 7x16 tyres. tyres. tyres. 10-20 2.9secs. 2.9 secs 3.1 secs. 3.0 secs. 3.35 secs. 3.4 secs. 10-30 5.7 5.7 6.1 5.8 7.0 7.3 10-40 8.6 8.6 9.1 8.75 10.5 10.8 10-50 11.62 11.64 12.7 11.9 13.7 13.85 10-60 15.0 15.1 16.5 15.65 17.35 17.7 10-70 19.13 19.5 20.2 20.4 23.0 22.15 10-80 24.75 25.7 25.4 27.7 30.35 Maximum Speeds. Direct 95 m.p.h. 93 m.p.h. - 89 m.p.h 92 m.p.h. - gear. Over- 97 m.p.h. 95 m.p.h. - 92 1/2 m.p.h 93 m.p.h. - drive. | ||