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).
Test report on the performance and characteristics of the EB.3844 cylinder head.
| Identifier | ExFiles\Box 124\2\ scan0282 | |
| Date | 17th December 1940 | |
| - 5 - The second cylinder head tested was EB.3844, which is the original smaller throat head with a comp ratio of 6:25:1: and 124 cc's capacity. This head required .015" Inlet and .015" Exhaust tappet clearances to give good slow running and idling, i.e; .006" more than the Exs.1383 head, but it is a much better head for detonations, this head also has a tendency to running after switching off, but is not so bad as Exs.1383. It must be borne in mind that it is a lower comp ratio and comp ratio has a big bearing on running after switching off, and detonations. Actually with this head fitted, the engine is very nearly as smooth as the B.lll Unit fitted to 2.B.50. Its performance is slightly better than the Exs.1383 head with none of its disadvantages other than requiring .006" more tappet clearance to obtain good slow running. (Continued) | ||