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).
Comparison table of choke sizes and depressions for a Size 3 carburetter.
| Identifier | ExFiles\Box 93\2\ scan0116 | |
| Date | 29th October 1935 | |
| x308 29.10.35. SIZE 3 CARBURETTER. | | Choke Size | Depression | |---|---|---| | Standard Duplex | 1.3/16" | 4.5" | | Daimlers Choke Size | | | | Singles to get power | 1.5/16" | 3" | | Largest chokes that can be got in | 1.13/32" | Wanted off Fisher Drawings | | ||