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 graph for a Phantom II engine comparing performance with different camshafts.
| Identifier | ExFiles\Box 13\2\ 02-page081 | |
| Date | 3rd June 1931 | |
| CURVE 1 PH. II POWER CURVES OPEN EXHAUST 4-6 COMP. RATIO A TWIN CARB. 1.30" CHOKES (STD COMP. RATIO)(R TYPE 110° CAMSHAFT) B " " " " ( " " ) ( STD CAMSHAFT ) B H P 150 130 110 90 70 50 30 R P M 500 1000 1500 2000 2500 3000 3500 A B R.A.G. / 3-6-31 | ||