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).
Instructions for modifying the ignition circuit on Wraith experimental cars to improve starting ability.
| Identifier | ExFiles\Box 164\5\ img337 | |
| Date | 31th March 1938 | |
| To HPS.{Horace Percy Smith - Experimental Factory Mgr} c. Rm{William Robotham - Chief Engineer}/Aym. c. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} 6017. BY/RD.4/B. 31.3.38. WRAITH. In order to enable us to prove the starting ability when a Rolls-Royce Coil is fitted, we propose to connect the ignition coil feed terminal to the switchbox, so that when the starter switch is operated, the ballast resistance is automatically short circuited. Will you please arrange to fit a cable to the Wraith experimental cars 40/36's Light Blue, from the Ignition Coil in-put terminal to the switchbox, at one end a Ross Courtney WE.503 should be fitted, and at the other end DW.640. It will be necessary to add to the switchbox - D.54862 - Distance Piece. 1 off. D.74939 - Angle Plate. 1 off. K.1804 - Cheese Head Screw. 1 off. K.9005 - Lock Washer. 1 off. K.4446 - Plain Washer. 1 off. These are all standard pieces. BY/RD. | ||