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).
Requesting the production of a new ignition distributor cam for the Wraith model for experimentation.
| Identifier | ExFiles\Box 168\3\ img121 | |
| Date | 21th March 1939 | |
| To RRG. c. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} BY/RD.8/B.21.3.39. WRAITH. DW.426. IGNITION DISTRIBUTOR. SECTION 8120. In order that a series of experiments may be completed, would you please produce for us, 1 Cam to drawing DW.949, blueprints of which are attached herewith, to replace DW.408. This new cam will give a make and break ratio of 70/30, and should be used in conjunction with a smaller radius on the face of the rocker block, reduced from .250 to .125. This however, can be arranged on the particular distributor that the test is made. The cam in question is a plain hexagon with a radius on the corners and as it will require to be used very little, we consider cyanide hardening will be ample, and we do not suggest that a master cam should be made or any elaborate tool equipment to produce this work. BY/RD. | ||