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 power output of an expanding choke carburettor versus a standard Phantom carburettor on a Phantom III engine with open exhaust.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan120 | |
| Date | 4th November 1929 | |
| V740 POWER OUTPUT WITH EXPANDING CHOKE CARB. COMPARED WITH STD PHANTOM CARB. ON A PHANTOM III ENGINE. OPEN EXHAUST. B.H.P. EXP. CHOKE CARB. STD PHANTOM CARB. R.P.M. CWH 4/11/29 | ||