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 a Wraith Cylinder Head drawing.
| Identifier | ExFiles\Box 8\6\ 06-page03 | |
| Date | 21th May 1937 | |
| SECRET. 619 Swoll See Lee BY.{R.W. Bailey - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} Fm. RHC.{R. H. Coverley - Production Engineer} HPS.{Horace Percy Smith - Experimental Factory Mgr} Mr Walker (Pattern Shop). Mr Goodall. DA.{Bernard Day - Chassis Design} E/JMR. E.7/HP.21.5.37. Wraith Cylinder Head. We are sending through a modification drawing for Wraith cylinder head LdC. 5684 on which the following changes have been made based on a consultation in the Foundry with Mr Walker and Mr Goodall. (1) All siamesed ports have been modified in shape in the fork to leave continuous sand from the cylinder crown to the water jacket roof of substantial thickness. (2) The single inlet ports on each end have been modified in shape to leave more sand between these ports and the contiguous exhaust ports. The section of the core has been increased by .150 in plan. (3) The minimum thickness of the water jacket core between the outer edge of the jacket walls and the outer stud bosses on the inlet side has been increased from .250 to .450. (4) The core bosses on the outer edge of the water jacket wall on the inlet side have been moved out to avoid interference with inspection, and this has the effect of continuing the side wall as a straight line on the inside. (5) The viewing plug holes on each end of the cylinder head inlet side have been moved out .45 and down .032 to allow the maximum clear view from one end of the cylinder head to the other. (6) Additional plug holes have been added in the top of the water jacket for clearing out and inspecting the passage ways between ports. (7) The central siamesed exhaust port has been modified in shape to increase the space in the fork between it and the contiguous stud boss. | ||