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).
Summary of car piston designs and their technical features.
| Identifier | ExFiles\Box 105\2\ scan0202 | |
| Date | 4th October 1929 | |
| X 2040. Hs.{Lord Ernest Hives - Chair} from Hs{Lord Ernest Hives - Chair}/Tsn. Hs{Lord Ernest Hives - Chair}/Tsn2/AD4.10.29. POSITION OF CAR PISTONS DESIGNS WE HAVE RECEIVED ARE :- S.S. Lec. 2737 - E.79500. Features :- (1) 4.125" long (Long skirt) Lec. showed 4.000" skirt; actually detailed 4.125". (2) Four rings all pinned. (3) Improved gudgeon pin retaining rings. (4) Thinner diagonal webs in head. CASTINGS NOT YET RECEIVED. E.79355 (Production edition of E.79500) (1) 4.125" long. (2) 5 rings - 3 pinned - as Phantom. (This is a Phantom piston merely lengthened). NOW ON PRODUCTION FITTED TO S.S. UNITS 5 & 15. Lec. 2729. Features :- (1) Invar struts either side, holding pin. (2) Cast alum. pads in contact with walls. (3) Bolted on cast alum. head. (4) 4 rings, all pinned. (5) 3.750" long, overall. DETAILED : E.79396 - 405. IN PROGRESS IN EXPL. SHOP. [Handwritten on left margin]: HP Pistn File [Handwritten at bottom]: Lec 2730 Fages had pistn above | ||