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).
Road test report detailing carburetter performance at altitude, fuel consumption, and criticisms of the car's gearing and steering.
| Identifier | ExFiles\Box 91\1\ scan0270 | |
| Date | 18th May 1936 | |
| -2- One of the main objects of the test was to try out the carburetter and induction system under high altitude conditions, and for this reason the Pic Veleta, which is the highest road in Europe and in the extreme South of Spain, was chosen. Unfortunately even in this latitude snow prevented an altitude of more than 7,500 ft. being reached. This, however, was sufficient to demonstrate that we are far better off than we were previously with the 4-carburetter scheme, though we shall probably have to follow the modifications made on the 20/25 H.P. to be clear of starting troubles under high atmosphere, high temperature conditions Both the petrol and oil consumptions were astonishingly good. We think that the petrol consumption cannot be taken as representative because owing to the different venting systems which we were trying on the carburetter, part of the time we were running with a mixture which was too weak for best performance. The car is definitely under-geared for Continental conditions. The maximum speed of approximately 89 m.p.h. is very quickly reached, and thereafter for mile after mile this speed can be maintained, almost irrespective of road surfaces. We recommend approximately a 4 : 1 rear axle ratio for the Continent. This would also help with petrol consumption. It is somewhat disconcerting to have to pay out about £8 for petrol in France during a day's run. The steering is undoubtedly the worst feature of the car and will be criticised. We accept that we ought to be no worse than if the La{L. A. Archer} Salle steering was fitted to the car, but on Continental roads we are certain that even with the La{L. A. Archer} Salle parts we should not be free from criticism, and it is appreciated that ultimately fundamental modifications may have to be made to the wheel movement to get the optimum results. On the other hand, even in its present condition the Ph.III steering is infinitely preferable to the Ph.II, and this should be remembered. | ||