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).
Design modifications for the Wraith III engine, focusing on cost reduction by replacing shouldered studs with plain studs.
| Identifier | ExFiles\Box 6\6\ 06-page156 | |
| Date | 5th March 1937 | |
| Leslie Fowey for Th DF. C. No. HPS.{Horace Percy Smith - Experimental Factory Mgr} SECRET. 600 E/JNR.{Charles L. Jenner}2/HP.5.3.37. Wraith III Engine. We send you herewith the following designs:- LeC.5552 showing the Fan and Bracket and the water connection from the front of the cylinder head. LeC.5555 showing the inverted plan of the crankcase and the oil gallery pipe. This clears all the work for the internal oil fittings. It will be noted on the specification of this engine that the shouldered studs for the cylinder head and main bearing caps are to be replaced by plain studs without waisting, and screwed in a tight fit in the crankcase, not up to the end of the thread but to a tubular gauge which governs the protruding length of stud. These studs reduce the cost. The stud bosses in the crankcase are left unchanged so that it will be easy to revert to the original studs if required. The modifications are shown on this drawing. LeC.5552) LeC.5555) herewith. E/JNR.{Charles L. Jenner} | ||