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 showing the variation of cam duration by tappet clearance on a 4 1/4 Litre Bentley engine.
| Identifier | ExFiles\Box 90a\1\ Scan008 | |
| Date | 1st May 1937 guessed | |
| 4 1/4 LITRE BENTLEY POWER DEVELOPMENT S.S. CAMSHAFT VARIATION OF CAM DURATION BY TAPPET CLEARANCE CAMSHAFT EB 1085 (STD 4 1/4 LITRE PRODUCTION) COMP RATIO 9:1 (EX20943) DUAL CARBS. STRAIGHT ON INLET PORTS ① IO 3°BT{Capt. J. S. Burt - Engineer} Eo 47°BB} STD TIMING HC 5°AB EL 6°AT} (APPROX) TIMING TAKEN 2.020 CLR X 1.187 THROTTLE BORE ② IN TAPPETS = .025" Ex " = .008" ③ IN " = .008" Ex " = .025" B.H.P B.M.E.P R.P.M. CTS{C. Trot Salt - Carburation} | ||