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).
Change to the Wraith III ignition timing.
| Identifier | ExFiles\Box 108\2\ scan0081 | |
| Date | 2nd May 1938 | |
| To By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} c. By/RD. c. By/CS. c. Mx.{John H Maddocks - Chief Proving Officer} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}9/MH.{M. Huckerby}2.5.38. WRAITH III IGNITION TIMING. Now that the hand control advance and retard has been deleted from the governor it is desirable not to have the static setting any earlier than TDC. by reason of the risk of firing back if the engine is started by hand. Slow running is also benefited by running at TDC. rather than before TDC. By means of a double governor spring which Rm{William Robotham - Chief Engineer}/RC.{R. Childs} has evolved a TDS. static setting can be used and yet have the right advance characteristic when running. Will you instruct, therefore, that the ignition setting on wraith III be TDC. in place of 5° BTDC. which is the present setting. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||