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).
Test report on brake performance, a comparison with a Hispano car, and details on clutch, carburettor, and exhaust system issues and modifications.
| Identifier | ExFiles\Box 182\M20\M20.1\ img031 | |
| Date | 1st May 1924 guessed | |
| (2) between the front and back wheels which naturally will not be the same from time to time, through wear, and also not equal at the different degrees of braking because they will vary with the relative elasticity of the front and back brake systems. On testing the 3 sets of brakes it was surprising how good they all were, but naturally my personal testing both for time and efficiency is very limited. At the end of the day two things struck me which were very gratifying, firstly that the Hispano was not a RR. car and would not be preferred by people usually using RR. cars for many reasons, including the stiff springing, carburation unreliable at slow speed demanding change of gear and noise, especially exhaust and tappets, but our R.{Sir Henry Royce} chassis even with the high compression EAC. engine which has not yet had the improvements introduced, was extremely good with the petrol-benzol mixture it was using, both for power, smoothness, and petrol consumption, and especially when compared with the Hispano for power at slow speed. The worst features noticed about the brakes was a certain amount of difference in the action of the servos, almost certainly due to the 'Ferodo' material, and which it is considered will be rendered more uniform by the use of 'Halo' or some slightly modified 'Ferodo'. The only other defects noticed on this test were (1) the clutch failing to come to rest especially going up a hill. This has already been dealt with so as to take advantage of the present harmful gravity. (untested) (2) a weak place in the large new carburetter which we believe can be easily cured by slightly altering the throat proportions as was found necessary with the Goshawk. We are modifying the exhaust pipe to our original 40/50 double type to do away with the losses at high speed of the present single and rather simple exhaust system. I think it is possible that we ought to have a very narrow patent covering the re-arrangement and combination of the parts as shown. Will HY.{Tom Haldenby - Plant Engineer} and Mr. Claremont kindly consider this? R.{Sir Henry Royce} [Handwritten note in right margin] RR & H-S | ||