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).
Table comparing the dimensional specifications for various engine crankshafts.
| Identifier | ExFiles\Box 65\4\ scan0217 | |
| Date | 2nd February 1928 guessed | |
| CRANKSHAFT DETAILS. X8010 X5010 X3531 Engine. Part No. | Phantom E.75216 | Sports Phantom. E.76546 | 1-G-1 E.18881. | Std. 20 HP. E.54064. | Stiffer 20 HP. E.51976. | India 111. LeC. 2480 No.of brgs. | 7 | 7 | 7 | 7 | 7 | 7 Outer dia. | 2.6245 | 2.6245 | 2.000 | 2.000 | 2.125 | 2.125 Inner dia. | 1.5000 | 1.750 | 1.250 | 1.250 | 1.250 | 1.375 Length of No.1 | 1.950 | 1.950 | 1.675 | 1.525 | 1.500 | No.2 | 1.500 | 1.500 | 1.050 | 1.050 | 1.000 | 1.150 No.3 | 1.500 | 1.500 | 1.050 | 1.050 | 1.000 | 1.150 No.4 | 2.500 | 2.500 | 1.800 | 1.550 | 1.500 | 1.575 No.5 | 1.500 | 1.500 | 1.050 | 1.050 | 1.000 | 1.150 No.6 | 1.500 | 1.500 | 1.050 | 1.050 | 1.000 | 1.150 No.7 | 3.000 | 3.000 | 1.800 | 1.800 | 1.750 | 1.800 Crankpins Outer dia. | 2.124 | 1.8735 | 1.500 | 1.500 | 1.625 | 1.500 Inner dia. | 1.125 | 1.125 | .875 | .750 | .750 | .875 Length. | 1.850 | 2.000 | 1.450 | 1.500 | 1.350 | 1.500 Crank radius. | 2.750 | 2.750 | 2.250 | 2.250 | 2.250 | 2.250 Nose. Outer dia. | 1.750 | 1.700 | 1.490 | 1.400 | 1.400 | Inner dia. | .750 | 1.000 | 1.100 | .625 | .625 | Length. | 3.200 | 2.75 | 4.750 | 2.500 | 2.500 | Length of pins and journals include fillets but not .010 facings. | ||