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).
Standardisation of main metering jets and choke torsion spring for the Phantom III carburettor to improve petrol consumption.
| Identifier | ExFiles\Box 171\5\ img016 | |
| Date | 23th November 1937 | |
| RR 755 (10H) (49988) 19/10/37 C.E.Co. LS COMPLETED 25.1.38. PHANTOM III STANDARDISATION OF PARTS Date Issued: 23.11.37. Sheet No. P.12. Drg. No. L.O.P.S. Description: MAIN METERING JETS .056. CARBURETTOR SECTION 5080. CHOKE TORSION SPRING E.{Mr Elliott - Chief Engineer} 89234. Purpose: Improvement on petrol consumption. Brief Report and Remarks: In conjunction with high pressure petrol pumps and small float needle seating the gain is 0.5 to 0.75 M.P.G. E.89234 choke torsion spring enables the car to be driven away with the engine cold, giving a better control of mixture. The spring is identical with the present standard but is reduced .450" to give increased initial load. Applicable to all carburettors marked R.S. When recommended for Introduction: IMMEDIATELY. Report References: Rm{William Robotham - Chief Engineer}/GR.{George Ratcliffe}13/WH.12.11.37. By: Rm.{William Robotham - Chief Engineer} Da.{Bernard Day - Chassis Design} Mx.{John H Maddocks - Chief Proving Officer} to By: Ry. Rm.{William Robotham - Chief Engineer} Da.{Bernard Day - Chassis Design} Mx.{John H Maddocks - Chief Proving Officer} Old Parts: Material, Labour, Burden, Total New Parts: Material, Labour, Burden, Total Increase in Cost £: Nil. Decrease in Cost £: G/Rb.{R. Bowen} 23.12.37. Production Position and Comments: Cost of Tools £: Messrs. Zenith state they have 37 completely finished carburettors and 18 partially assembled, together with 180 springs and 52 extra jets in stock. To modify the springs, change the jets and scrap those in stock as they cannot be re-calibrated. Messrs. Zenith quote a total cost of £5.2.0. To modify carburettors in stock at R.R. new metering jets can be obtained for 3d. each and new springs for 1d. each. SEE OVER FOR RHC{R. H. Coverley - Production Engineer}'S COMMENTS. Authorisation to Proceed. Introduce on the 15th Chassis in D Series. Sg.{Arthur F. Sidgreaves - MD} Signature Date: 17-1-38. Hs.{Lord Ernest Hives - Chair} Signature Date: 17/1/38 | ||