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).
Preliminary tests of a dual Stromberg carburettor on a Wraith engine, noting poor distribution and requesting drawings for modifications.
| Identifier | ExFiles\Box 7\4\ X 608 Carburetter-page49 | |
| Date | 13th December 1938 | |
| 608 abca 1033 To By/Ald.{F. Allwood - Experimental Design} Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation}6/JH.13.12.38. DUAL CARBURETTER (STROMBERG). We have carried out preliminary tests on a Wraith engine, using the twin choke type AA{D. Abbot-Anderson}25 carburetter, mounted on the mock up induction pipe EX.27979. This drawing shows the same system applied to the centre box, as that used on standard Wraith with a single carburetter. Distribution was extremely bad under this condition. Normal bends, immediately after the throttle were then inserted, two types being tried Rm.{William Robotham - Chief Engineer}564. First the gradual bend and then sharp bends. Both types although showing different characteristics gave improved distribution but nowhere near required standard. Increasing lengths of rises did not improve matters. We now wish to modify the mock up pipe, to embody the principle shown on Rm.{William Robotham - Chief Engineer}564. This turns the carburetter through 90°, and thus increases the distance of the throttle from the centre ports. Will By/Ald.{F. Allwood - Experimental Design} please make the necessary drawings showing detachable bends of the 'gradual' type. At the same time fitting a new dividing wall in the centre box, which will take the form of a curved plate sweated in position. Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation} | ||