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 for engine components including main bearings, connecting rods, pistons, and camshaft.
| Identifier | ExFiles\Box 126\1\ scan0066 | |
| Date | 24th January 1938 | |
| - 3 - BY/Ald.{F. Allwood - Experimental Design}1/G.24.1.38. MAIN BEARING. No.1 - 2.478 x 1.19/32 - 2 Dowels .250 long. No.2 2.5405 x 1½ " " " No.3 2.6655 x 1½ " " " No.4 2.6855 x 1.11/16" " " " CONNECTING RODS. Forged finish - steel. Big ends white metalled in steel shells. No shims. NOTE: Big end will pass through cylinder block. Rod rifle drilled for gudgeon pin lubrication. Cylinder walls are lubricated from an oil 'Spit' hole in the big end, which coincides with a hole in the crankshaft once per rev. (T.D.C.) Big end clearance .001 - .003 Big ends 2.1/8" dia. x 1⅜" long. PISTON. Anodically treated alum. (Bath of sulphuric oxalic acid). Length of piston 4.1/32 and 2.237 from centre line of gudgeon pin to top of piston. 2 compression and 2 scraper ring above pin. Pin pressed in and retained by cheese headed screw. Pin .8557 dia. Pin offset .097 off. cylinder centre line to nearside. Gudgeon pin hole is .0005 smaller on lock screw side. This allows boss on opposite side to slip during expansion due to heat. Remove piston from top of cylinder. CAMSHAFT. Material C.I. Machined only on bearings and cam profiles. | ||