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 analysis memo detailing brake horsepower figures and discussing Brooklands lap times.
| Identifier | ExFiles\Box 5a\5\ 05-page196 | |
| Date | 24th December 1931 | |
| HW/Wal/MA.24.12.31. Cont'd At 70 M.P.H. Carb. 6 B.H.P. Comp. Ratio. 4 B.H.P. Cut Out. 7 B.H.P. 19 B.H.P. on 70 M.P.H. or 37% increase. At 80 M.P.H. Carb. 11 B.H.P. Comp Ratio. 4 B.H.P. Cut Out. 7 B.H.P. 22 B.H.P. on 80 M.P.H. or 50% increase. As regards performance with these increased powers, 18-G-4 lapped Brooklands at 78.43 M.P.H. and did over the half mile with an average of 81.47 M.P.H. which is about what we shall get (S/52/MS.3.8.31.) In quoting Brooklands figures it should be noted that 18-G-4, our last 16,000 mile car has only a Brooklands lap speed of just over 70 M.P.H. and yet frequently ran up to 80 M.P.H. in France and a maximum of 84 M.P.H. actual was recorded under favourable conditions. It would therefore be fair to consider the proposed car with a lap speed of 80 M.P.H. as an 88 M.P.H. proposition. The only alterations from 2-G-4 to give this result would be pistons, cut out control, and throttle edge slow runner on the carburetter. HW/WH. Attached : Ms.51. | ||