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).
The performance improvements of the Phantom II engine when fitted with a twin Solex carburettor, including feedback from Sir Henry Segrave.
| Identifier | ExFiles\Box 13\3\ 03-page186 | |
| Date | 21th January 1930 | |
| x7080 To R.{Sir Henry Royce} (held up) From Hs.{Lord Ernest Hives - Chair} c. to BE. W.R. c. to E.{Mr Elliott - Chief Engineer} Da.{Bernard Day - Chassis Design} c. to HY.{Tom Haldenby - Plant Engineer} PN.{Mr Northey} PHANTOM II CARBURETTORS AND PERFORMANCE. We have recently sent a report showing the increase in BHP on a Phantom II engine when fitted with a twin Solex carburetter. We have now a car running on the road with this scheme fitted. The increase in performance is very marked, the acceleration and hill climbing at all useful speeds is greatly improved. The increase in performance is much greater than the increase of Phantom I over Phantom II. Sir Henry Segrave, who has been running an Hispano and now has on order a Phantom II, recently ran a Phantom II trials car similar to 18-EX for two or three days. Whilst generally he was very pleased with the car, he criticised the acceleration and snap get away. We know from timed tests that the Phantom II is not so good as Sir Henry Segrave's Hispano. With the twin Solex however we can equal the Hispano figures and one can also appreciate that the snap acceleration at normal speeds is more instantaneous due to having no automatic air valve. We have in the past, always considered that an automatic expanding carburetter was essential for our requirement but judging from the results with the Solex on the Phantom II this is open to question. The torque curve shows that we can | ||