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).
Performance graph comparing standard, 50% larger, and 100% larger chokes on a China CIS unit.
| Identifier | ExFiles\Box 179\2\ img086 | |
| Date | 22th December 1931 | |
| R.M. 61 COMPARISON OF STANDARD 50% LARGER AND 100% LARGER CHOKES. CHINA CIS UNIT ALL TESTS C.O. OPEN 20G & 1S. EXHAUST SYSTEM C/R 874 CAMSHAFT E.57177 110.5° 22/12/31 Ex IN 6 .020 CLCE 40.5 44 CARB AS ON 20G & 1S 50% LARGER CHOKES & AIR VALVE 100% LARGER CHOKES B.H.P. R P M INDUCTION DEPN B M E P 6120 5110 4100 390 280 170 060 | ||