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).
Application of raised crown pistons to a single cylinder unit.
| Identifier | ExFiles\Box 123\5\ scan0067 | |
| Date | 26th August 1938 | |
| 1044. By/Ald.{F. Allwood - Experimental Design} from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}6/R.26.8.38. Single Cylinder. Regarding the raised crown pistons you have recently drawn for us for the B.60 engine, we should like to apply it for a start to the single cylinder unit (3.25") bore in conjunction with B.60 type of cylinder head. The actual requirements are as follows:- (a) Existing cylinder head B.60 type (EB.3477) gives a compression ratio of 6.4 and 3 1/4 bore piston to be schemed with raised crown to give 7.4:1 compression ratio. (b) In conjunction with the flat topped piston, the cylinder head EB.3477 modified to give a compression ratio of 7.4:1 in a manner we will discuss with you. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||