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).
Descriptions of air flow and pressure difference tests for various cylinder heads and valves.
| Identifier | ExFiles\Box 17\6\ Scan137 | |
| Date | 24th August 1933 | |
| -3- Hs{Lord Ernest Hives - Chair}/Std.11/MA.24.8.33. (5) Air flow/valve lift curve (pressure difference across valve constant for large valve cylinder head (E.83906):- This curve was taken keeping pressure difference across valve constant and increasing valve lift from zero to 1" lift. (6) Air flow/press difference across valve curves for large valve Cyl. Head (E.83906) with and without regrinding lips on valves The inlet valves (E.83904) as fitted to cylinder head (E.83906) had a regrinding lip on them (Diagram (3)) which was hardly a good streamline shape. This lip was removed and one set of valves and curves taken to compare with (3). (7) Air Flow/press. difference across valve curve for special head - Standard E.B5358 fitted with inlet valves smaller than standard (1.7" instead of 1.9" dia.):- This test was carried out exactly as (2) at full lift only. (8) Air flow/press. difference across valve curve for 8 litre Bentley 4 valve "single port" head :- This test was carried out on a Bentley 8 litre cylinder block received from Bentley Motors Ltd., exactly as (2) - at full lift only. (B) Rolls-Bentley. (1) Air Flow/press difference across valve curve for standard R head EB228 This curve was XXXX taken at pressure differences to give flows corresponding to engine speeds of 3750-2500 RPM. and at full valve lift. (2) Air flow/press difference across valve curve for Japan head - E.56604:- This curve carried out exactly as (1). | ||