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 large versus small valves, detailing BHP and BMEP against RPM for an engine with a 4.9 compression ratio.
| Identifier | ExFiles\Box 182\M19\ img204 | |
| Date | 17th June 1931 guessed | |
| Hs.{Lord Ernest Hives - Chair} 380 COMPARISON LARGE & SMALL VALVES 4.9 CR{Mr Cra???ster / Mr Chichester} 114° R CAMSHAFT OPEN EXHAUST SINGLE CLAUDEL CARB H.{Arthur M. Hanbury - Head Complaints} 380 BOUNCE Valve Timing Diagram: IN: 12, 60 EX: 65.5, 14 AXIS LABELS: B.H.P. B.M.E.P. R.P.M. TABLE - BASE OF SEAT DIA: | INLET | EXHAUST LARGE VALVES | 2.1" | 1.95 SMALL VALVES | 2.0" | 1.85 LEGEND: LARGE [solid line] SMALL [dashed line] | ||