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 BHP and BMEP vs RPM for Twin Zenith and Standard carburettors with different camshaft configurations.
| Identifier | WestWitteringFiles\W\May1931-August1931\ Scan035 | |
| Date | 11th July 1930 | |
| TWIN ZENITH CARBURETTER ON (JAPAN JVG6) V914 COMPARISON WITH STD CARBURETTER ZENITH RUN WITH 26 m/m CHOKES. SMALL BORE INDUCTION PIPE COMPLETE STANDARD 25HP EXHAUST SILENCING SYSTEM STANDARD 110° AND LONG DURATION 112° CAMSHAFTS 5.25:1 COMPRESSION RATIO AXIS LABELS: B.H.P RPM B.M.E.P GRAPH LABELS: TWIN ZENITH 112° CAMSHAFT TWIN ZENITH 110° CAMSHAFT STD CARB 112° CAMSHAFT STD CARB 110° CAMSHAFT OTHER: W.S. 11-7-30 | ||