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).
Engine cylinder head design, detonation issues, and potential improvements including valve and camshaft design.
| Identifier | ExFiles\Box 134\2\ scan0080 | |
| Date | 3rd October 1936 guessed | |
| - sheet 2 - We have a drawing of a modified cylinder block in hand for this purpose. Referring back again to the lack of smoothness associated with the high power head, it is found that the exhaust valve runs very hot, and tends to set up high speed detonation, and the present unit can only be run continuously at high speed with freedom from detonation by using a sodium cooled exhaust valve. We think that further single cylinder research is required on this head before it can be seriously considered for a main engine. One proposal we have drawn out is to lift the inlet valve position sufficiently to allow the combustion chamber above the exhaust valve to be scoured during the inlet stroke, and we propose to modify a head for a test along these lines. With regard to a full scale application, we have taken some steps to look into this, and there appears to be no inherent difficulty in making such an engine that can easily be produced. With regard to the question of multiple inlet valves, I think we could go a long way on one valve before such a move became necessary. We have been inclined in the past to be somewhat fierce on our cam design, and there is something in hand here that could be taken advantage of. We anticipate being able to get some result in this direction from our valve gear investigations. We are eagerly awaiting some results from the 6 cylinder overhead camshaft unit, as this scheme has the virtue of providing more valve capacity in the present length of engine and should show us the ultimate possibilities as regards breathing of the overhead valve type. In conclusion it, therefore, appears that our single cylinder work at the present time can be confined | ||