Hand-drawn diagrams illustrating modifications to the Phantom III tappet mechanism.
| Identifier | ExFiles\Box 96\1\ scan0402 | |
| Date | 18th August 1934 guessed | |
| 2" ³⁄₈" Copper pipes Remaining drain holes plugged. Three ⁵⁄₁₆" dia holes in each tappet block. MODIFICATIONS TO PHANTOM III TAPPET MECHM SB {Mr Bull/Mr Bannister} | ||
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).