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).
Graph comparing engine performance (BHP and BMEP vs RPM) for different valve timing configurations found by experiment.
| Identifier | ExFiles\Box 182\M19\ img203 | |
| Date | 17th June 1931 guessed | |
| H.S. 379 COMPARISON OF TIMING APPROXIMATING TO LEC.2918 & BEST TIMING FOUND BY EXPERIMENT A TIMING APPROX. TO LEC. 2918 1 1/4" SHAFT B BEST TIMING R.{Sir Henry Royce} ENGINE. CAMS 110° SHAFT C AS B BUT TAPPET CLEARANCE ADJUSTED TO GIVE BEST RESULTS. CLAUDEL CARB. 4.3 C.R. ALUM. HEAD. OPEN EX. Graph Labels: Curves: A, B, C Left Y-Axis: B.H.P. Right Y-Axis: B.M.E.P. X-Axis: R.P.M. Timing Diagram A: A, 12, 14, EX 65.5, IN 60 Timing Diagram B: B, 17, 18, EX 69, IN 56 Timing Diagram C: C, 18, 9, EX 236, IN 250, 58, 48 Bottom Note: .020 TAPPET CLEARANCE | ||