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).
Note regarding raised crown pistons for 4 1/4-litre Bentleys, specifically for R. Summers' chassis B.58.GA.
| Identifier | ExFiles\Box 89\1\ scan0257 | |
| Date | 31th March 1939 | |
| 261a. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} Rm.{William Robotham - Chief Engineer} H/R.{Sir Henry Royce} 31.3.39. Re raised crown pistons for 4 1/4-litre Bentleys - R.{Sir Henry Royce} Summers' Chassis no B.58.GA. file 236. | ||