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).
Power curve graph for the Super Sports Engine N°SS-3 with a 116° camshaft, comparing performance with a 110° camshaft.
| Identifier | ExFiles\Box 92\2\ scan0021 | |
| Date | 19th September 1928 | |
| V423 POWER CURVE WITH 116° CAMSHAFT. SUPER SPORTS ENGINE N°SS{S. Smith}-3. COMP. RATIO = 4.5 CLAUDEL HOBSON CARBURETTOR HOT SPOT IN ACTION (WATER AT 75°C) OPEN EXHAUST. 116° CAMSHAFT TO E77322. (N.B. NOZZLE E77799 REMOVED FROM INDUCTION PIPE). BRAKE HORSE POWER. RPM. OF ENGINE. Graph Annotations: 110° CAMSHAFT (NOZZLE FITTED IN INDn PIPE). PROBABLE CURVE WITH NOZZLE REMOVED (110°). 116° CAMSHAFT. Valve Timings Table: VALVE TIMINGS. (.020 TAPPET CLEARANCE). | | 116° CAMSHAFT. | 110° CAMSHAFT. |--- |--- |--- | INLET OPENS. | 21° AFTER TDC | 14° AFTER TDC | INLET CLOSES. | 45° AFTER BDC | 34° AFTER BDC | EXHAUST OPENS. | 36° BEFORE BDC | 34° BEFORE BDC | EXHAUST CLOSES. | AT TDC. | 2° AFTER TDC | ||