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).
The Big Bore 20/25 model, a reverse control modification, and the future programme for the Bentley Big Bore engine.
| Identifier | ExFiles\Box 30\1\ Scan266 | |
| Date | 1st December 1935 | |
| - 6 - Big Bore 20/25 (contd) Department for the testing, so that everyone could see exactly what is being aimed at. Material was, at this Conference, authorised for 200 chassis in "M" series. GENERAL Control for Reverse A modification has been issued for this, which should get over the trouble previously reported. BENTLEY Big Bore Engine - Future Programme This is still in hand and is not yet completed. The car in France has now practically finished its 15,000 miles test, after which it will be returning to W. Troubles have been experienced with engine bearings, but every effort is being made to achieve satisfactory results in time for production. Solid hall metal bearings are being tried, i.e. without shells. Supercharger No further work is being carried out on this at the present time, but the possible use of a supercharged 6-cylinder Big bore Bentley has not been lost sight of. | ||