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 customer feedback on a high compression cylinder head and comparing it to other engines.
| Identifier | ExFiles\Box 27a\1\ Scan207 | |
| Date | 3rd January 1935 | |
| [handwritten] X4013 [/handwritten] To Rolls-Royce Ltd. Derby................ Rm.{William Robotham - Chief Engineer} Levallois Sr7/ET.3.1.35 Re: HIGH COMPRESSION CYLINDER HEAD I was very interested to read your memo Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}7/KW31.12.34 and the information given [handwritten] by the various [/handwritten] power curves attached. It certainly tends to prove that the high compression cylinder head should improve the performance of the 20/25 H.P. more than it has done in the case of Mr. Poberejsky's car. I am sorry it will not be possible for me to comply with your desire to let Hancock have this cylinder head off [strikethrough] Mr Po- [/strikethrough] berejsky's car to try on 21-G-IV, for the very excellent reason that this customer has taken delivery of his car and, to use his own words, "thinks the improvement simply remarkable"; he declares that it is a different car now that it has this new cylinder head on it. Needless to say this is very much like a Doctor who gives a patient a piece of sugar, telling him it is some wonderful dope; providing the patient believes the doctor he feels much better although, in reality, the Doctor has not done anything to him.! There is no doubt that the performance of this car is slightly improved from the 40 Kms. per hour, but it is by no means as good as 21-G-IV. As regards your paragraph re the Hispano scheme for silencing the tappets, I shall go into this question this afternoon and keep you informed. There is no doubt that the 12 cylinder Hispano engine has been considerably quieted down of late and that it is now a quieter unit than our present Phantom II. On the other hand you may be interested to know that they are having a lot of trouble with pistons, which all have to be changed after about 20.000 Kms. I expect my sister will be coming over to Europe sometime this spring and will keep you informed. Sr [Signature] | ||