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).
Testing modifications to induction and exhaust pipes related to engine heating.
| Identifier | ExFiles\Box 75\2\ scan0226 | |
| Date | 26th May 1921 | |
| Contd. -4- Hsl/LG26.5.21. ------------ not good. We have tested out the scheme suggested by Springfield. We found that we got a great improvement with it. Upon analysing this out we found that the improvement was not due to the heating but due to the fact of having the 1" pipe through the centre of the present standard induction pipes. We tested the amount of heat we got by taking the 1" pipe from the centre and fixing up on the outside with the usual connections to the exhaust. We could then feel the temperature of this pipe or measure it. We found that the temperature of the pipe when it was outside the induction pipe never got above 100°C when the engin was running at 500 R.P.M. full power which is the speed we need the heat. If we ran light loads, of course, the heat was very much less. We altered the arrangement of the exhaust pipes so that instead of taking a connection from the end of the box and getting an interchange of the mean pressure from the three cylin- ders, we took a connection from numbers 1 and 6 cylinder exhaust elbows so that there would be a greater variation in pressure and therefore a greater interchange of the exhaust. We also increase the diameter of the exhaust pipes leading out into the 1" pipe. We found by this we could get up to 200°C, but even with this increased heat, we could not get a very great improvement with the heat. The big advantage we got was due to the 1" pipe not to heat. We then altered four induction pipes and put this 1" pipe through the centre. With No.1 we get excellent results. No.2 " " very good results. No.3 " " good results. No.4 " " poor results. contd:- | ||