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).
Compression pressure, volumetric efficiency, and airflow tests on Phantom II cylinder heads.
| Identifier | ExFiles\Box 17\6\ Scan136 | |
| Date | 24th August 1933 | |
| -2- He/Std.11/MA. 24.8.33. (1) Compression pressure and volumetric efficiency determination. The compression pressure on each of two cylinders was measured at various engine speeds on engine itself by cutting out cylinder in question and measuring pressure by means of a non return valve in plug hole and a Bourdon pressure gauge. Calculations for volumetric efficiency shown in appendix. (2) Air Flow/press diff. across valve curves for Standard P.II Cylinder head (E.83538) at various lifts:- These curves were taken at 1/3 mean, and full lifts with pressure differences across valve to give flows corresponding to 2750 - 3500 R.P.M. engine speeds. (3) Air Flow/press difference curves for large inlet valve P.II cylinder head (E.83906) at various lifts:- These curves were taken exactly as in (2). Note. After above tests, since results showed that similar results were produced at 1/3 mean, and full lifts, all further tests, other than Air flow/valve lift curves, were carried out at full lift. (4) Air Flow/press difference curves for Standard across valve P.II cylinder head (E.83538) using shrouded valve (Diagram(1)) in different positions to compare effectiveness of opposite halves of valve:- A standard inlet valve (E.82458) was fitted with a shroud as shown in Diagram (1) and curves were taken with - (a) Shrouded half of valve towards centre of combustion chamber. (b) Shrouded half of valve away from centre of combustion chamber. | ||