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).
Engine connecting rod lengths and ratios for different engine types.
| Identifier | WestWitteringFiles\V\October1930-February1931\ Scan203 | |
| Date | 13th January 1931 guessed | |
| (2) The actual rod lengths are given in the following table: STROKE. | CON. ROD. | ENGINE. | RATIO. ------- | --------- | ------------ | ------ 4.5 | 7.95 | Standard 25. | 1.77 4.5 | 8.45 | LeC. 2756. | 1.88 5 | 10 | Improved 25. | 2 LeC. 2756. is an intermediate scheme which was instructed having larger crankpins and grooved bottom half crankcase. The rods we should like to try on an existing engine would be 9" long, and hence 1.05" packing would be required under the cylinder block. E.{Mr Elliott - Chief Engineer} | ||