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).
Letter discussing the introduction of a butterfly valve to the hot spot induction pipe to improve performance in cold weather.
| Identifier | ExFiles\Box 50\3\ Scan150 | |
| Date | 1st August 1921 | |
| H.H. 235A.(100 T) (S.H. 159. 11-8-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2600 X4305 To R.R. of America Inc.) For the attention of OY. c. to CJ. c. to Hs.{Lord Ernest Hives - Chair} RL/G11.8.21. X.4305 - RE HOT SPOT INDUCTION PIPE. I have received your letter with reference to the hot throttle. It will be noticed that in the most recent arrangement we have introduced a butterfly valve in the throttle to maintain the heat more constantly, and to make the 1/2" pipe leading to the throttle more effective. We have every confidence that this arrangement will do much towards making the cars more satisfactory with the poor petrol and cold weather, together with the effective use of the radiator shutters to maintain the water temperature around the cylinders and to keep the engine house warm in winter. We regret the long induction pipe, but there seems no means of getting rid of this until we are able to move the carburetter. It has occurred to me that owing to less intricate passage provided by the straight butterfly valve, this scheme will permit of a longer length of heated pipe without undue heat to the gas and therefore will effectively shorten the induction pipe. This is what we have got in mind of the scheme for the higher position of the carburetter. So far as we have gone the temperature of the existing type of throttle exhaust heated, is about twice the number of degrees F.{Mr Friese} that it is with water heating. It is wonderful what good effect the present small amount of heat obtained by the water has in the present instance, if the water is kept as hot as possible. R.{Sir Henry Royce} | ||