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).
Electrically timed lap speed tests of a Streamline Bentley at Montlhéry.
| Identifier | ExFiles\Box 90\1\ Scan064 | |
| Date | 28th December 1933 | |
| To Sg.{Arthur F. Sidgreaves - MD} from Ha/Rm.{William Robotham - Chief Engineer} Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} c. to Hy.{Tom Haldenby - Plant Engineer} c. to Ev.{Ivan Evernden - coachwork} c. to Hn.{F. C. Honeyman - Retail orders} file X 261 Ha/Rm.{William Robotham - Chief Engineer}9/KW28.12.33. Streamline Bentley - Tests on Montlhery. ------------------------------------ To conclude the tests on this car enumerated in Ev{Ivan Evernden - coachwork}1/KT.4.12.33, it was taken over to Montlhery in order to get an electrically timed lap speed. The figures obtained were as follows, the conditions only being moderately good owing to ice and snow on the track. OPEN TOURING CAR. Windscreen up, lap speed 138 kms. per hr., which is 86.5 mph Windscreen down, " 146.5 " " " " " 91 " STREAMLINE CAR. " " 157.6 " " " " " 97.94 " ALL TESTS C.O. OPEN. For the purpose of these tests the streamline car was fitted with the aerolite pistons, high compression head previously reported on, and the 11/41 axle. We attach a road wheel horse power curve of this car compared with the standard unit. Now that we have these figures we can estimate exactly what increase in m.p.h. the additional H.P. obtained from this engine are worth. With the standard power this car would have lapped Montlhery at 95 m.p.h., which is the figure anticipated from the wind tunnel test, and confirms the stop watch speed obtained on Brooklands. We think that a still air speed of 98 m.p.h. from a fully equipped saloon car with a 3 1/2 litre power unit only is a unique result that has not previously been achieved. | ||