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).
Advantages of a new cast iron piston design for potential use in car 49GB.
| Identifier | Morton\M22\ img011 | |
| Date | 21th March 1912 | |
| To EH & E.{Mr Elliott - Chief Engineer} from R.{Sir Henry Royce} 3. There will, however, be a fresh one to be made in cast iron exactly like those tested in the aero engine, but with the piston pin in the correct position. Such a piston will suit the existing rods. These pistons appear to have the following advantages over anything else we have tested. (1) Light weight. (2) Cooler crown, which does not burn up the oil, but permits it to flow back round the rings, hence - (3) Gas tightness. (4) Increased power, due to this cooler surface not heating the incoming gases. (5) Inexpensive to construct. In conclusion, I believe we only have these pistons suitable for our standard engine in steel. These could be fitted to car 49GB, pending the instructions from Mr Elliott for cast iron ones. F.H.R. [Upside down text at bottom of page:] H'K 5377 (200 11) (2 V 'H'K 21-3-12) (C' 100) | ||