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).
Specification sheet for different types of multi-ringed pistons for aero and chassis applications.
| Identifier | ExFiles\Box 35\2\ scan 019 | |
| Date | 31th July 1917 | |
| H.M. Sta. A (570 H) S.D. 442. 9-2-17) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 1905 To X 2749 EFC3/T31.7.17. MULTI-RINGED PISTONS Aero. X. 2209A - Seven Ringed Pistons (Low compression). X. 2209B - " " " (High " ). Chassis. X. 2369A - Piston with 6 Upper Rings and one Scraper and with no skirt. X. 2369B - Ditto with skirt. X. 2809A - Pistons with 6 Upper Rings and one Scraper, skirt, and 6 rings pinned. X. 2809B - Ditto with 4 instead of 6 rings pinned and .2" gap instead of .4". | ||