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 Stromberg JX4 and Zenith Down Draught carburettors on a 6 cylinder 80 x 120 engine.
| Identifier | ExFiles\Box 122\1\ scan0144 | |
| Date | 1st June 1930 guessed | |
| 6 cyl. 80 x 120. STROMBERG JX4 Zenith Down Draught. BHP. RPM. Pints/BHP/Hr | ||