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 airflows with standard and increased valve lifts against pressure difference for a Bentley head model.
| Identifier | ExFiles\Box 86\1\ scan0041 | |
| Date | 30th November 1933 guessed | |
| SHEET 3 BENTLEY AIR FLOW - CU.FT. / MIN. PRESS. DIFFERENCE ACROSS VALVE - INS. HG. COMPARISON BETWEEN AIRFLOWS WITH (1) STD. VALVE LIFT - .400" (2) INCREASED VALVE LIFT - .450" USING L.E.C. 3673 HEAD MODEL (VALVE DIA: - 1.5") INCREASED LIFT - 0.450" STANDARD LIFT - 0.400" NOTE:- TESTS CARRIED OUT WITH CYL. BARREL IN POSITION. | ||