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 comparing the acceleration of a Phantom (12EX) with Solex and RR carburettors.
| Identifier | WestWitteringFiles\T\2January1929-June1929\ Scan105 | |
| Date | 5th February 1929 | |
| CAR SPEED (M.P.H.) TIME (SEC) PHANTOM ACCELERATION (12EX) SOLEX AND RR CARBURETTER SOLEX RR 5-2-29 | ||