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).
Specifications and component updates for Silver Wraith engine units.
| Identifier | ExFiles\Box 161a\3\ scan0160 | |
| Date | 5th May 1939 | |
| -9- HPS{Horace Percy Smith - Experimental Factory Mgr}/WSC.{W. S. Cassel}6/BA.5.5.39. Silver Wraith Units. W.R.No.1. New Unit, for which specification has been issued in HPS{Horace Percy Smith - Experimental Factory Mgr}/WSC.{W. S. Cassel}6/BA.14.4.39 3.250 dia bore. - Below is a summary of the main items required. (a) Crankcase top and lower halves in L.5. alloy. (b) EB.4410 Crankshaft damper. (c) EW.2170 Pistons - Aerolite to ECD.1269. (d) EW.2179 Cylinder Block with EW.2180 Liners. (e) Strengthened Exhaust Valves to PD.403 Motor Component produced inlet valves. (f) EX.S.768 Camshaft, incorporating SCD.663. (g) Oil Filter to SCD.1038. Otherwise the engine is practically a Wraith III type, the specification should be carefully checked over and the position reviewed with the object of arriving at a completion date, this should be given at the next meeting. We understand that the top half crankcase castings have now been delivered. W.R.No.2. Late B.V.No.6 converted into the Wraith Ripple type, by fitting the following; (a) EW.2177 Cylinder Block produced in Nickel Chrome Molybdenum. (b) EW.2170 Pistons - Aerolite. Otherwise the specification is to HPS{Horace Percy Smith - Experimental Factory Mgr}/WSC.{W. S. Cassel}1/BA.19.4.39 We anticipate passing to test this unit on Tuesday next, it must be noted that as the correct pistons are not available, and we are informed by Rm{William Robotham - Chief Engineer}/CTS{C. Trot Salt - Carburation} that we shall not have same before the 12th, we are to fit EB.2441 B.II type Pistons. contd..... | ||