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).
Status report on debatable points concerning the Bentley's carburettors, induction system, air intake silencer, and engine breathing.
| Identifier | ExFiles\Box 3\4\ 04-page277 | |
| Date | 15th May 1933 | |
| To Hs.{Lord Ernest Hives - Chair} X 4553 Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}2/KT.15.5.33. BENTLEY POSITION. The following is the position of a number of debatable points on the Bentley. (1) Carburetters. We have not yet received the model carburetters from the S.U. Company. (2) Induction System. We have satisfied ourselves that the water heated induction system will work. On the other hand, we have no design for this system, and it is doubtful whether the warming up would be quick enough with the thermostat radiator control. We have now completed a number of experiments on the exhaust heated hot spot and have satisfied ourselves that we can obtain a compromise with the double hot spot, whereby we reduce the amount of exhaust gas until we get a compromise which gives us barely enough heat for slow running and rather too much for high speed work. We think it would be better to fit this to the first 200 sets, (rather than the single hot spot scheme instructed for the first fifteen cars). It is very essential to run this system in France to make sure that it produces no unexpected troubles. (3) Air Intake Silencer & Breather. We have now found by experiment the right size and shape of bend to cause the minimum disturbance to the distribution. Before the end of the week we shall have established a satisfactory air silencer. It is very essential, however, that these parts should be run in France to ensure that we do not adversely affect the petrol consumption, and from some preliminary work we have done on the track it may slightly affect the maximum speed of the car. Engine Breathing. This is tied up with the air intake silencer, and as yet we have no knowledge whether it will prove successful under road conditions. We consider the breathing of the engine is of vital importance because it dictates the oil leaks which are likely to | ||