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 a twin Zenith carburettor against a standard chassis carburettor with different camshafts.
| Identifier | ExFiles\Box 102\5\ scan0060 | |
| Date | 22th May 1930 | |
| TWIN ZENITH CARBURETTER ON 'JAPAN'. COMPARISON WITH STD CHASSIS CARBURETTER. ZENITH USED WITH 26 M/M CHOKES - SMALL BORE INLET PIPE - 112° & 116° CAMSHAFTS - 5.25/1 COMPN RATIO. OPEN EXHAUST. B.H.P. R.P.M. B.M.E.P. TWIN ZENITH 112° CAMSHAFT. TWIN ZENITH 116° CAMSHAFT. 112° TWIN CARBS. 116° TWIN CARBS. STD CHASSIS CARB. 116° CAMSHAFT STD CHASSIS CARB. 112° CAMSHAFT 112° 20HP CARB. 116° 20HP CARB. | ||