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 Solex twin-choke carburettor against the standard RR carburettor on a Phantom II.
| Identifier | WestWitteringFiles\U\January1930-April1930\ Scan060 | |
| Date | 22th January 1930 | |
| SOLEX TWIN CHOKE CARBURETTER ON PHANTOM II (32 MM CHOKES IN SOLEX CARBURETTER.) POWER AT ROAD WHEELS. IGNITION TIMING. MAG. 18° B.T.D.C. BATTY 12° B.T.D.C. CUT-OUT CLOSED. CHASSIS N° 19 Ex. ROAD WHEEL B.H.P. ENGINE R.P.M. LEGEND: R.R. CARBURETTER 19 Ex. - - - - - X SOLEX ,, - O | ||