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 weights and moments of inertia for B.60 and Flat 12 engine components.
| Identifier | ExFiles\Box 132\2\ scan0188 | |
| Date | 26th October 1940 guessed | |
| 5. APPENDIX WEIGHTS. B.60 Flat 12 (Ph.III size) Piston, pin, rings. 1.58 lbs. 1.34 lbs. Connecting rod - Big end 1.12 lbs. Forked 2.0 Plain 1.27 little end .44 lbs. .8 .75 MOMENTS OF INERTIA. B.60 Flat 12 (Ph.III size) Reciprocating parts at each crankpin. .0132 .0277lb.in sec.2 Rotating parts of conn. rods. .0147 .0429 (fork + plain) Crankpins (2" dia.) .0126 (2.25"dia) .019 Journals: front (2.75"dia) .00648 (2.75"dia) .00654 rear .0122 .00654 centre .00724 .00654 inter .00533 .00403 Crankshaft webs - unbalanced .0181 .0273 Ph.III { (fully balanced - .085 (half balanced - .0528 B.60 - Integral ba- lance weights .0441 - Flywheel 4.7 lb.in sec2 5.7 lb. in sec2 | ||