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).
The development and merits of side valve engines compared to overhead valve engines, referencing American automotive trends.
| Identifier | ExFiles\Box 134\2\ scan0047 | |
| Date | 18th July 1935 | |
| -6- Side Valve Unit. Two years ago, when I was in America, Janeway was saying that side valves were so bad for breathing that American manufacturers would shortly be forced to overhead valves. His contention does not seem to have been borne out by recent developments. We do not know of a single new American car that has been brought out with overhead valves in the last two years. On the contrary, we do know that the H.P. curves of the Buick, the Ford, and the Packard compare very favourably with what we can do with the 20/25 of the same compression ratio, cylinder size, and with the same degree of slow running. The Americans have decided very emphatically that the side valve engine is by far the cheapest to produce. It seems wrong that with single cylinder facilities at our disposal, we should not know the relative merits of the best that can be done with the side valve compared with the overhead valve engines of the 25 HP. type. Our conclusions, therefore, are that as a first objective we ought to make a side valve and an overhead camshaft single cylinder unit. We suggest that E.{Mr Elliott - Chief Engineer}, Wd.{Mr Wood/Mr Whitehead}, HEC. and Rm.{William Robotham - Chief Engineer} meet to discuss the question in general, including the facilities for manufacture that it will be possible to provide. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Att: Hs{Lord Ernest Hives - Chair}/Bmth.20/KW.15.7.35, with print Hs.{Lord Ernest Hives - Chair}2068. Hs{Lord Ernest Hives - Chair}/Bmth.6/KW.20.6.35. with prints Hs.{Lord Ernest Hives - Chair}2064/5/6. Hs{Lord Ernest Hives - Chair}/Bmth.7/KW.29.6.35. Hs{Lord Ernest Hives - Chair}/Bmth.10/KW.4.7.35. | ||