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).
Weight comparison between 3½ and 4¼ litre Bentley engines and a breakdown of weight alterations for the 4¼ litre chassis.
| Identifier | ExFiles\Box 88\3\ scan0192 | |
| Date | 3rd April 1936 guessed | |
| Sheet (3). Weight of 3½ litre Bentley Engine and Gearbox complete. 719 lbs. (Does not include fan, sparking plugs, brake equaliser gear, or oil). Weight of 4¼ litre Bentley Engine and Gearbox complete. 702 lbs. (exactly as above). Difference ... ... ... ... 17 lbs. Alterations in Weight with introduction of 4¼ litre chassis - Item. Increase lbs. Decrease lbs. Engine 17 Deletion of cut-out 5.5 Deletion of propellor shaft damper 12.75 Added petrol filter on rear cross member 1.5 Stiffened floorboard 1.0 2.5 35.25 ∴ nett decrease = 32.75 lbs. | ||