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).
Dimensions of pistons and rings for a Bentley 6-cylinder unit after endurance and general running tests.
| Identifier | ExFiles\Box 3\6\ 06-page281 | |
| Date | 16th June 1924 | |
| BENTLEY 6 UNIT. DIMENSIONS OF PISTONS AND RINGS - 100 HOURS ENDURANCE AND 100 HOURS GENERAL RUNNING PISTON DIAMETERS EB 1299 EB 1025 Des. Size. 3.247 Dia +0/-1/2 DIMENSIONS TAKEN ON SKIRT PISTON | A | B | C 1 | 3.2470 | 3.2488 | 3.2493 2 | 3.2478 | 3.2485 | 3.249 3 | 3.2478 | 3.249 | 3.250 4 | 3.2474 | 3.2486 | 3.249 5 | 3.2472 | 3.2488 | 3.2498 6 | 3.2475 | 3.2483 | 3.2485 DIMENSIONS TAKEN AT RIGHT ANGLES TO GUDGEON PIN WIDTH OF RING GROOVES Des Size .0875 +1/-0 AND .150 +1 PISTON | TOP | 2ND | 3RD | SCRAPER 1 | .0885 | .0885 | .0885 | .1505 2 | .0883 | .0885 | .0885 | .1504 3 | .0883 | .0885 | .0885 | .1501 4 | .0884 | .0885 | .0885 | .1507 5 | .0883 | .0885 | .0885 | .1507 6 | .0885 | .0885 | .0885 | .1507 THICKNESS OF RINGS Des. Size .0855 AND .148 +0/-1/2 PISTON | TOP | 2ND | 3RD | SCRAPER 1 | .0843 | .0848 | .0848 | .1477 2 | .0855 | .0852 | .085 | .1478 3 | .0843 | .085 | .085 | .1478 4 | .085 | .085 | .085 | .1479 5 | .085 | .0852 | .085 | .1478 6 | .085 | .085 | .0849 | .148 WIDTH OF RING GAP Des. Size .075 AND .010 TOP | 2ND | 3RD | SCRAPER .079 | .079 | .080 | .015 .079 | .078 | .078 | .022 .078 | .078 | .078 | .022 .080 | .090 | .082 | .018 .080 | .078 | .078 | .024 .080 | .078 | .080 | .021 | ||