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).
Urgent internal memo requesting a comparative test on small versus large exhaust valves to investigate Wraith III valve seat failures.
| Identifier | ExFiles\Box 10\3\ 03-page179 | |
| Date | 30th September 1938 | |
| c Lufkin γ URGENT. To HPS.{Horace Percy Smith - Experimental Factory Mgr} from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}2/WH.30.9.38. 654. WRAITH III VALVE SEAT FAILURES. In order to definitely establish whether the small exhaust valve (std.) is any worse than the original large dia. exhaust valve in respect of the above trouble, will you please carry out the following on the small valve head you have available for the job. Nos. 1, 2 and 3 cylinder exhaust valve throats tobe opened out to EW.1296, 1.4 dia. and E.61299 exhaust valves fitted. Nos. 4, 5 and 6 cylinder exhaust valves retained as at present with small valves The above is very urgently required, likewise the new cylinder heads EW.1949. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||