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).
Modifications to car WMB-11 to remove detonation and gather experimental data.
| Identifier | ExFiles\Box 109\5\ scan0141 | |
| Date | 20th July 1939 | |
| 664 PRIVATE. Sg.{Arthur F. Sidgreaves - MD} from Rm.{William Robotham - Chief Engineer} Rml8/R.20.7.39. Your Car - WMB-11. As discussed with you on the telephone, we decided that the most satisfactory way of removing the detonation from your car, without spoiling its performance, was to alter the ignition advance characteristics. This has been done. A special experimental cylinder block has been fitted so that we can get information on cylinder bore wear. Low rating springs and front roll rod have been fitted. Rm.{William Robotham - Chief Engineer} | ||