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).
Blueprint graph comparing the performance of large versus small valves.
| Identifier | ExFiles\Box 13\2\ 02-page105 | |
| Date | 17th June 1931 guessed | |
| Hs.{Lord Ernest Hives - Chair} 380 COMPARISON LARGE & SMALL VALVES 4.9 C.R. 114° R CAMSHAFT OPEN EXHAUST, SINGLE CLAUDEL CARB. B.H.P. B.M.E.P. R.P.M. EX IN 12 14 50 65.5 BASE OF SEAT DIA. INLET EXHAUST LARGE VALVES 2.1" 1.95 SMALL VALVES 2.0" 1.85 LARGE SMALL BOUNCE | ||