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).
Effects of various modifications on a car's speed, including changes to the undershield, wings, cutout, tail, and hood.
| Identifier | WestWitteringFiles\Q\2-July1927-September1927\ 111 | |
| Date | 8th September 1927 guessed | |
| contd :- -3- (2) Undershield. This is clearly hardly worth while except as a meand of keeping the car clean. As fitted it is surprisingly easy to manipulate. (3) Front wings. The latest type of front wings only reduce the max. speed by 3.5 m.p.h. or almost 50% less than the previous type of sports wing fitted to 10-EX. They will require a slight modification to protect the front of the rear springs however. (4) Cutout open. We estimate that opening the cutout on the present car is equivalent to an increase at the clutch of at least 20 HP. at 2800 r.p.m. This gives us 4 m.p.h. in maximum speed. (5) Tail. The tail is worth while as it increases the maximum speed of the car by 3 1/4 m.p.h. (6) Hood. The hood is very reasonably efficient with regard to windage. (7) Body general. Removing the running boards, fitting the tail, new front wings and windscreen, have given us 7.4 m.p.h. because we have no more engine horse power at present than in the previous tests. CONCLUSIONS. The possibilities of further speed increase appear to be as follows :- contd :- | ||