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).
List of specifications and modifications for the Wraith III, No. 5 Unit.
| Identifier | ExFiles\Box 155\2\ scan0156 | |
| Date | 23th September 1937 | |
| Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}1/RR.23.9.37. 5. Wraith III. No.5. Unit. (28.G.VI.) An extra .125 dia. hole in each crankpin, original .2187 hole being retained. W/L. main bearing with RR.56 shims. Big end bearings in A.C.b with single centre hole. No. 1 - 6 tappet bushes in I/C inclined 45° No. 7 -12 tappet bushes in V/C Cylinder liners, No. 1, 2, 3 and 4 Hepolite. No. 5 and 6 Centricast. Inlet valves S.65 material. Rs.{Sir Henry Royce's Secretary}540 Swedish wire springs coiled at RR. Rm.{William Robotham - Chief Engineer}400 top washers. Bottom tappets in I/C blanks produced by C. & A Smith. Conical base housing for push rod, latter likewise conical. Vauxhall copy camshaft giving a lift of .325 (Rs.{Sir Henry Royce's Secretary}608) Unhardened S/ZNA timing gears RR. ignition distributor. Relief valve spring 1.88790 High pressure. Ex.28174 Low pressure. AC.bye pass oil filter inlet from main press outlet to rocker pressure. Extra cam keyway fitted to give finer timing. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||