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).
Power curve comparison graph for two different induction systems on a B4 Unit engine.
| Identifier | ExFiles\Box 93\2\ scan0064 | |
| Date | 1st July 1935 | |
| TEST N° I CURVE N° I INDUCTION SYSTEMS JULY 1935 B4 UNIT (STD. BENTLEY.) POWER ① STANDARD BENTLEY SYSTEM 2 1³/₈ S.U. CARBS. ON 1.500 BORE PIPE ② SINGLE 1⁵/₈ S.U. CARB ON SAME PIPE HORIZONTALS COMP. RATIO 6.5:1 CAMSHAFT - BENTLEY B.H.P. R.P.M. B.M.E.P. C.T.S | ||