Graph comparing airflow through various Phantom II cylinder heads and an 8 Litre Bentley head.
| Identifier | ExFiles\Box 31\2\ Scan118 | |
| Date | 29th August 1933 guessed | |
| PHANTOM CURVE 6 FLOW THRU PORT CU.FT./MIN COMPARISON OF VARIOUS PHANTOM II HEADS & 8 LITRE BENTLEY HEAD (1) ----- 8 LITRE BENTLEY HEAD (4 VALVES / CYL.) (2) ----- PH. II HEAD - E.8390G INLET VALVE DIA. - 2.0" (THROAT.) (3) ----- STD. PH. II HEAD - E.83538 INLET VALVE DIA. 1.9" (THROAT.) (4) ----- STD. PH. II HEAD - E.83538 INLET VALVE DIA. 1.7" (THROAT.) NOTE:- ALL CURVES AT FULL LIFT i.e. P.II - .480" BENTLEY - .335" PRESS. DIFFERENCE ACROSS VALVE - "Hg. | ||
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).