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).
Comparison table of component metrics, possibly weights or costs, for different engine sizes.
| Identifier | ExFiles\Box 136\2\ scan0131 | |
| Date | 28th July 1939 | |
| Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls}7/MH.{M. Huckerby}28.7.39. | | PD.477 5.6-litres | .875 3.7 litres | .815 3-litres | .71 2 litres. | |---|---|---|---|---| | Castings | 26.5 | 20.5 | 17.5 | 13.4 | | Gear Trains | 43.5 | 28.8 | 23.3 | 15.5 | | Change Speed & Selector | 15.5 | 15.5 | 15.5 | 15.5 | | Bearings | 4.7 | 3.6 | 3.1 | 2.4 | | TOTAL | 90.2 | 68.4 | 59.4 | 46.8 | | ||