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 valve lift against crankshaft displacement for Rudge, Bentley, and modified camshafts on a 500cc unit.
| Identifier | ExFiles\Box 133\1\ scan0018 | |
| Date | 2nd February 1936 | |
| G 12 500 c.c. RUDGE UNIT VALVE LIFT DIAGRAMS BORE - 3.346" STROKE - 3.464" CR{Mr Cra???ster / Mr Chichester} = 7.3:1 CAMSHAFT I.O. I.C. E.O. E.C. OVERLAP RUDGE A 28°E 48°L 50°E 25°L 53° MOD. I B 19°L 48°L 42°E 8°L 11° BENT. C 4°E 50°L 50°E 7°L 11° .020" TAPPET CLCE. VALVE LIFT (INS) CRANKSHAFT DISPLACEMENT (DEGS.) EXHAUST Rudge Bentley Mod. I INLET T.D.C. B.D.C. JLE{J. Lee Evans - Chassis Test Manager} 2-2-36 | ||