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).
Dynamometer and road test comparison of a Solex twin choke carburetter against the standard carburetter on a Phantom II.
| Identifier | WestWitteringFiles\U\January1930-April1930\ Scan058 | |
| Date | 22th January 1930 | |
| To R.{Sir Henry Royce} (Held up) From HS{Lord Ernest Hives - Chair}/AJL. c. to SS.{S. Smith} Wor.{Arthur Wormald - General Works Manager} c. to L. Da.{Bernard Day - Chassis Design} c. to aV. FH. x7080. x7770. [Text below is underlined and crossed out] SOLEX TWIN CHOKE CARBURETTER ON PHANTOM II. REPORT ON ROAD MILEAGE AND ROAD PERFORMANCE. We have carried out a dynamometer test on a Phantom II car fitted with a Solex twin choke carburetter as compared with the same car fitted with the standard R.R. carburetter and induction system. The Solex carburetter is the same one that was tried on a Phantom I chassis (12-EX) at the beginning of last year; a rough copper induction pipe with exhaust heated jacket was made to suit the Phantom II unit. The B.H.P. curve shows a remarkable power increase, at its maximum at 1250 and 1500 r.p.m. (15%). The effect of this increase in power is felt on the road to a remarkable degree. The acceleration up to 45 m.p.h. is improved up more by the addition of this carburetter than the Phantom II was improved over Phantom I. From any speed 5 m.p.h. upwards the response to the acceleration is immediate; there is no lag at all. On our standard hill climbing tests in none of which a maximum speed of more than 60 m.p.h. is reached, the increase in performance is very marked - on Ticknall Hill the time is reduced from 61 seconds to 56 and on Pistern Hill, which is a lower speed climb (max. speed 35 m.p.h.) the time for the climb is reduced from 64 secs. to 55 secs. No serious attempt has as yet been made to refine the | ||