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 engine output based on different valve sizes, camshaft timings, and carburettor setups.
| Identifier | ExFiles\Box 102\5\ scan0136 | |
| Date | 24th June 1932 guessed | |
| RM.{William Robotham - Chief Engineer} P.24 COMPARISON OF VALVE SIZES W.W. 1 1/4" CAMSHAFT 4.78 C.R P II UNIT OPEN EXHAUST --- VALVES 2" THROAT. HEAD MACHINED TO GIVE A MINIMUM CLEARANCE OF .2" ..... ROUND VALVE — STD. 1.90 THROATS HEAD STANDARD .013 TAPPET CLEARANCE Valve Timing Diagram A: Ex 58 IN 54 3 12 B. TIMING. 7° EARLIER CURVE LABELS: CLAUDEL TIMING A TWIN CARBS 1.4 CHOKES TIMING B CLAUDEL TWIN DEPN TWIN CARBS DEPN CLAUDEL AXIS LABELS: B.H.P. R P M B.M.E.P LBS/SQ.IN INDUCTION DEPN. INS. Hg. | ||