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).
High compression heads, fuel quality in France, and the effects of leaded petrol on exhaust valves.
| Identifier | ExFiles\Box 27a\1\ Scan312 | |
| Date | 11th September 1935 | |
| W/P - Sr. X1245 Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}1/KW.11.9.35. With reference to our conversation re the high compression heads and pinking in France, attached is correspondence I have had with the Ethyl Export Corporation. This is very satisfactory in that it indicates that without doubt the Esso petrol in France will very shortly be as good as that obtainable in England, which will permit of the use of the high compression head. We recommend that you try the head you have at present over there on Azure, as we anticipate that if this is 78 octane the higher ratio should be quite a passable proposition. At the same time we think that if you make representations to the Esso people, pointing out that they are inferior to Azure and that they are not suitable for the latest Bentley head, it is possible that they may expedite the increased lead content. At the same time, we would point out that lead has a disadvantageous effect on exhaust valves, and we anticipate that in the case of customers who habitually drive their cars hard on Esso, a certain amount of seat deterioration will take place. In order to overcome this we are considering standardising stellited valves, and we are sending out a set of these to be fitted to B-1-CW so that we can have your opinion on them. These will probably be despatched in about 10 days' time. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Att: Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}8/KW.3.9.35. Letter from Ethyl Export Corp. dated 4.9.35. 9.9.35. | ||