Typed letter discussing poor running, pre-ignitions, and a knock in car 7 CA.
| Identifier | Morton\M11\ img192 | |
| Date | 19th August 1919 | |
| To EH. from R. {Sir Henry Royce} Copy to CJ. " " BN. {W.O. Bentley / Mr Barrington} " " EFC. {E. Fowler Clarke - Electrical Engineer} " " DA. {Bernard Day - Chassis Design} 7CA OPINIONS RE KNOCKS ORIGINAL X 682. RE CAR 7 CA. X 3413 I am very pleased with your explanation of the poor running of 7 CA, but I have never before remembered having preignitions on our car engine through over-heated plugs, and thought the Lodge plugs were quite safe from this trouble, except in aero engines where the duty of mean pressure is enormously greater. Regarding the knock in 7 CA. Mr. Elliott had the impression that it was in the coupling under the floorboards. I had the impression that it was a piston or little end. You will be able to settle this probably by examination of the pistons parts. R. {Sir Henry Royce} | ||
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).