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 Brake Horsepower and Depression curves from experiments with various choke sizes on a Half Solex twin carburetter.
| Identifier | ExFiles\Box 13\3\ 03-page350 | |
| Date | 18th October 1931 guessed | |
| DEPRESSION WITH VARIOUS CHOKE SIZES PH. II EXPERIMENTS USING HALF SOLEX R.M. P.29 TWIN CARBURETTER 1.6 DIA. THROTTLE DIFFUSER DIA. P DENOTES B.H.P. CURVE D DENOTES DEPRESSION CURVE B.H.P. R.P.M. DEPN. INS. HG. TIMING AS ON R.M. P.28.4 TABLE: NO. OF CURVE | CHOKE DIA | DIFFUSER AREA | THROUGH CHOKE FREE AREA 1 | 1.100 | .350 SQ IN | 60 SQ IN 2 | 1.080 | .35 SQ IN | 56 SQ IN 3 | 1.030 | .35 SQ IN | 48 SQ IN 4 | .900 | .35 SQ IN | 28 SQ IN | ||