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).
Test report on modifications to S.U. carburetter float chamber covers, detailing changes in fuel delivery rates.
| Identifier | ExFiles\Box 27a\2\ Scan219 | |
| Date | 27th July 1933 | |
| X2677 To E.{Mr Elliott - Chief Engineer} from Ha/WB.{Mr Brazier/Mr Bell} Ha/WB.{Mr Brazier/Mr Bell}13/KT.27.7.33 MODIFICATION TO S.U. CARBURETTER FLOAT CHAMBER COVERS - FURTHER TO REPORT Ha/WB.{Mr Brazier/Mr Bell}8/KT.15.7.33. Covers fitted with .125" Needle Seats used on No.5 Test Bed Engine These tests were performed with a pump delivering 171 pts/hr. at 2000 r.p.m. with full Bensport suction, and delivery systems. The only apparent modification from standard on these covers was the increase of the valve seat to .125". The tests were also repeated with the previously modified covers. Delivery Pts/Hr. Reduction % Open Pipe. With Modifications 2E. Float Chamber Covers complete. .125" needle seats. 171 156 8.75 3E. Needles Removed. Float Chamber Covers only - No needle seats - Standard. 171 167 2.34 4E. [strikethrough] 171 169 1.17 2F. Float Chamber Covers complete - .093" Needle Seats - Standard. 171 153 10.5 3F. As for 2F. Needles Removed. 171 163 4.8 Float Chamber Covers Previously Modified - Tests Repeated 2D. Float Chamber Covers Comp. .250" Ports. .125" Needle Seats. 6 Release Ports. 171 160 6.45 3D. Needles Removed. 171 169 1.17 4D. Float Chamber Covers Only - No Needle Seats - 171 171 0 The maximum pressure at 2000 r.p.m. registered 5.2 lbs/sq.in. at this setting whereas with the previous pump the max. pressure was 4.7 lbs/sq.in. Cont'd.{John DeLooze - Company Secretary} | ||