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 testing and modification of a Bentley aluminium cylinder head.
| Identifier | ExFiles\Box 86\1\ scan0060 | |
| Date | 25th April 1934 | |
| To RHC.{R. H. Coverley - Production Engineer} X219 Hs{Lord Ernest Hives - Chair}/CTS.{C. Trot Salt - Carburation}10/KW.25.4.34. BENTLEY CYLINDER HEAD. Cyl. Head. We send you herewith Hs.{Lord Ernest Hives - Chair}1372 Aluminium Will you please produce one of these for test purposes, as we wish to see how the larger inlet valve behaves in an alum. head. The inserts suitable for this head are shown on Hs.{Lord Ernest Hives - Chair}1373-4 and the valves Hs.{Lord Ernest Hives - Chair}1375 and EB.1325. Tests on the previous Aluminium Head to EB.1237 have shown that firstly, the compression ratio of 7.35:1 causes too much detonation with the present design; and secondly that useful power may be gained by using a 1.500 dia. inlet valve. Also, for further development work, will you please modify the existing cyl. head EB.1237, which was produced in cast-iron. The same valves and seats are suitable as will be used on Hs.{Lord Ernest Hives - Chair}1372, but in this case the material for the inserts should be Tungstone steel. Hs{Lord Ernest Hives - Chair}/C.T. Salt. | ||