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).
Secret memo from 'Sg' to 'Hs' discussing the performance effects of lower compression on 'SS' cars.
| Identifier | ExFiles\Box 65a\3\ scan0092 | |
| Date | 30th July 1929 | |
| S/W. SECRET. x7770 To Hs.{Lord Ernest Hives - Chair} from Sg.{Arthur F. Sidgreaves - MD} Sg{Arthur F. Sidgreaves - MD}6/D30.7.29. re 'SS{S. Smith}' Cars. Referring to R3/M26.7.29 and Sg{Arthur F. Sidgreaves - MD}6/D23.7.29, I shall be glad to hear from you regarding comparative tests that have been made. You will see R.{Sir Henry Royce} mentions that the chassis with the lower compression at most would only have a loss in improvement of performance of 2% to 3%, whereas PN.{Mr Northey} tells me that he understood from you on the telephone that the reduction in compression would bring the performance of an 'SS{S. Smith}' down to about the same as that of a good Phantom, so that I am a little in the dark. I am sure you must have made comparative tests which will show the position clearly and if, as the result of your tests, you feel that lower compression is something of which we ought to approve for special cases, I should be very pleased if you could arrange a trial of a car, the performance of which has not been lowered, and one on which it has. Possibly, however, the improvements which you have, as I expect, been able to make during the last few weeks regarding the chief point that we were all troubled about have reduced the necessity of a possible reduction in compression even for special cases. MADE AT CROMPTON | ||