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).
Comparative study of piston designs 'Gos I' and 'Gos II' against a '40/50' model, with dimensioned drawings and tables of area and ratio calculations.
| Identifier | ExFiles\Box 77\3\ scan0263 | |
| Date | 17th February 1924 | |
| Top Drawing (40/50): Dimensions: 4.250, 1.000, 2.250, 1.000, 1.000 Dia., 4.500 Dia. Label: 40/50 Middle Drawing (Gos I): Label: Gos. I Dimensions: .750 Dia., .725, 1.200, .725, 2.650 Bearing Bottom Drawing (Gos II): Label: Gos II Dimensions: 2.700, .800, 1.100, .800 Bottom Dimensions: .650, 1.400, .650, 3.000 Dia. Side note: 40/50 RATIO. Table Data: Columns: Gos I | Description | 40/50 | Gos II Row 1: .707 | PISTON AREA. | 15.9 | 7.07 Row 2: 1.485 | GUDGEON AREA | 4.25 | 2.02 Row 3: .281 | RATIO. GUDGEON/PISTON | .267 | .287 Row 4: .900 | SMALL END BUSH AREA | 2.250 | .825 Row 5: .453 | RATIO OF GUDGEON AREA | .53 | .407 Row 6: 1.485 | GUDGEON IN PISTON AREA | 2.000 | 1.200 Row 7: .547 | RATIO OF GUDGEON AREA | .47 | .593 Calculations (Bottom Right): To make Gos II. same ratio as the 40/50 = 2.700 x .53 = 1.43 2.700 x .47 = 1.27 2.70 Stamp (Top Right): ROLLS-ROYCE, LTD. P. [illegible] DEPT. RECEIVED 14 SEP 1923 | ||