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).
Performance graph comparing high lift rockers, showing B.M.E.P. against R.P.M. for different valve lifts and carburettors.
| Identifier | Morton\M19\ img237 | |
| Date | 9th August 1931 guessed | |
| COMPARISON OF HIGH LIFT ROCKERS RM{William Robotham - Chief Engineer} P 20 SMALL VALVE HEAD 4.75 C/R INLET VALVE THROAT 1.680 114° CAMSHAFT E.{Mr Elliott - Chief Engineer} 82448 TIMING AS IN RM{William Robotham - Chief Engineer} P 19 VALVE LIFT .525 VALVE LIFT .470 CLAUDEL CARB R.R TWIN CHOKE CARB 1.4 THROAT NO APPRECIABLE DIFFERENCE IN LOW SPEED M.E.P. WITH VALVE LIFT. Left Y-Axis: B.M.E.P. Right Y-Axis (Vertical): INDUCTION DEPN. INS. HG. Right Y-Axis (Vertical): B.M.E.P. LBS/SQ.IN. X-Axis: R.P.M. | ||