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).
Fuel and oil consumption for a post-war chassis, suggesting experiments with engine compression.
| Identifier | Morton\M22\ img014 | |
| Date | 10th October 1916 | |
| (R) 49GB Contd. X.2565 - Post-War Chassis -10) 194 (28) X.3056 Fuel Consumption. Earlier in this description I have suggested that a slow moving air valve is advantageous for petrol consumption, because it has a tendency for the driver to avoid enriching the mixture so as to get the engine to run nicely when opening the throttle. The same effect appears to be brought about by keeping the low jet slightly on the rich side, though I am not sure that this is so manifest. I would like experiments to be made to see whether under average road conditions, the change in the size of the induction pipe or the compression ratio, makes any material difference in the petrol consumption. I have the distinct feeling that a moderate increase of compression is decidly benificial. X.2634 During these experiments the consumption of oil can also be recorded and in passing I should like to point out that 49-GB, is quite remarkable in the small quantity of oil it uses and the absence of dripping oil on the road when standing or coming to rest. (29) Consumption. 49-GB is a particularly soft engine. It does not appear to have any harsh speeds and it suggests that it is possible to increase the compression from whatever this is - 10% or 20% if it was found to be any decided benefit in power or consumption. Finally. - These suggested investigations will be exceedingly useful for all furture cars and are not necessarily confined to the first 300 cars only. | ||