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).
Implementation of two compression ratios and improvements to the SS chassis.
| Identifier | ExFiles\Box 19\7\ Scan142 | |
| Date | 29th May 1929 | |
| X 740 Hm.{Capt. W. Hallam - Head Repairs} from R.{Sir Henry Royce} SECRET. R3/M29.5.29. C. to Sg.{Arthur F. Sidgreaves - MD} Hs.{Lord Ernest Hives - Chair} Wor.{Arthur Wormald - General Works Manager} E.{Mr Elliott - Chief Engineer} X 740 X 8040 40/50 - TWO COMPRESSION RATIOS I appreciate your memo. Hm{Capt. W. Hallam - Head Repairs}5/W27.5.29. The trouble with two compression ratios as standard is that they get so frightfully mixed up, and it is increasingly difficult with an engine having a turbulent head, except that it is no longer necessary to change the pistons, but to change the head. The point I have in mind is that the lower compression engine would go to the people who were not owner drivers, and as I feel that the passengers very rarely notice the engine impulses, I fear we should not gain anything worth the trouble and confusion. It is the owner driver who seems to grumble at the roughness of the engine, and the owner driver is also the man who wants the powerful engine. If I am mistaken please correct me. Regarding the SS.{S. Smith} generally I am extremely pleased to hear that you think the three principle objects of the improvements introduced into this chassis have achieved their results in quite a distinct degree. Many people thought this hardly possible, but as you know we have for a long time had many of the points in mind, and I regret we have now been able to introduce them earlier. Knowledge without action seems of little value. One point is extremely noticeable in connection with cars generally, namely, that it is necessary to have the engines well run in, and free, before comparing one with another, as it seems to make an immense difference in the smoothness, and also in the power available. R.{Sir Henry Royce} | ||