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).
Graph showing the throttle characteristics of an S.U. carburetter on a Kestrel VI engine at various altitudes.
| Identifier | ExFiles\Box 31\5\ Scan285 | |
| Date | 1st March 1934 | |
| KESTREL VI ENGINE S.U. CARBURETTER CURVE 3 CURVE SHEWING THE THROTTLE CHARACTERISTIC OF THE S.U. CARBURETTER TO BALANCE OUT THE RICHENING DUE TO ALTITUDE WHEN RUNNING AT CONSTANT POWER FROM GROUND LEVEL UP TO FULL THROTTLE HEIGHT. 550 B.H.P. MAINTAINED BY INCREASING THROTTLE OPENING. THE WEAKENING CHARACTERISTIC OF THE THROTTLE CURVE COMPENSATES FOR THE RICHENING DUE TO REDUCED DENSITY AT ALTITUDE. % RICH 15 12 9 6 3 % WEAK 3 6 9 12 FULL THROTTLE JET SETTING FLOW REDUCTION DUE TO THROTTLE CHARACTERISTIC FLOW INCREASE DUE TO ALTITUDE RESULTANT CURVE. CONSTANT FLOW AT ALTITUDE. SPEC CONS CURVE CONST R.P.M. 2500 CONTINUATION OF THROTTLE CURVE. THROTTLING DOWN FROM 550 BHP AT GROUND LEVEL B.H.P. 400 450 500 550 600 650 700 750 800 10000 9000 8000 7000 6000 5000 4000 3000 2000 1000 GROUND LEVEL PTS/HP/HR .700 .650 .600 .550 .500 .450 | ||