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).
Hand-drawn conceptual diagram for a valveless 2-stroke engine and a silent exhaust system.
| Identifier | ExFiles\Box 79\2\ scan0094 | |
| Date | 2nd February 1921 guessed | |
| DIRTY CYLINDERS IMPOSSIBLE. EVERYTHING IS DRAWN OUT FROM 1st STROKE TO LAST. SPIRAL WORM INCREASING IN PITCH DIAPHRAGM 4 CYLINDER 2 STROKE VALVELESS No CRANKCASE COMPRESSION NEEDED. GIVES SAME No OF EXPLOSIONS AS AN 8 CYL. 4 STROKE 22 MILES TO THE GALLON GUARANTEED ON A 40/50 ROLLS ROYCE DEAD SILENT X 3352 | ||