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 comparison graph of a Twin Zenith carburettor against a standard chassis carburettor with different camshafts.
| Identifier | WestWitteringFiles\U\May1930-July1930\ Scan057 | |
| Date | 22th May 1930 | |
| TWIN ZENITH CARBURETTER ON 'JAPAN' COMPARISON WITH STD CHASSIS CARBURETTER. ZENITH USED WITH 26 m/m CHOKES - SMALL BORE INDN PIPE - 112° & 116° CAMSHAFTS - 5.25/1 COMPN RATIO. OPEN EXHAUST. V869 B.H.P. B.M.E.P. R.P.M. TWIN ZENITH 112° CAMSHAFT TWIN ZENITH 116° CAMSHAFT STD CHASSIS CARB. 116° CAMSHAFT STD CHASSIS CARB. 112° CAMSHAFT 112° TWIN CARBS. 116° TWIN CARBS. 112° 20 H.P. CARB. 116° 20 H.P. CARB. Aeh 22-5-30 | ||