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).
Design improvement for 40/50 HP chassis pistons by using concave crowns to reduce knocks.
| Identifier | WestWitteringFiles\C\May1919\ Scan12 | |
| Date | 19th May 1919 | |
| To DH.{D. Henderson - Showroom} from E.{Mr Elliott - Chief Engineer} Copy to: " PAL " ELL " DY.{F R Danby} " EFC. ORIGINAL. RE 40/50 H.P. CHASSIS PISTONS FOR LONG CONNECTING RODS.- FOR REPAIR WORK. X.3559 With reference to the aluminium pistons to be used with the standard long type connecting rods for the 40/50 H.P. engine, it is thought that the design might be improved by the use of concave piston crowns. The object is to minimise the piston knocks. The use of a concave crown allows the bearing surface of the piston to be longer, the extra length being added on the top portion of the piston. The position of the piston pin will be relatively lower. Would you kindly have a modified scheme of the piston for the long rod prepared, incorporating the above, in accordance with Mr. Royce's instructions, and send to West WitteringHenry Royce's home town for his criticism. E.{Mr Elliott - Chief Engineer} D 19 MAY 1919 RECEIVED | ||