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).
Effects of changing the rod length to crank radius ratio on engine forces and flywheel inertia.
| Identifier | ExFiles\Box 13\9\ 9-page8 | |
| Date | 19th April 1934 guessed | |
| (2) If my conclusions are not correct perhaps E.{Mr Elliott - Chief Engineer} and H/TSN. will write to me again on the subject. I read Mr. Elliott's memo. - r & : - = crank radius, l = rod length. If this is correct my calculation shews 33% difference between ratio 2 = 100% ratio 1.75 = 133%, or equal to reducing the weight of the piston rings and little end by 1/3rd., and also forces are 50% greater, needing 50% more inertia in flywheel for a given speed change due to this cause (i.e. not power impulses - gas pressures.) R.{Sir Henry Royce} | ||