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).
Blueprint figures, cylinder head comparisons, and petrol consumption for the 4 1/4 Litre Bentley.
| Identifier | ExFiles\Box 82\4\ scan0267 | |
| Date | 27th February 1936 | |
| W/S - Cx.{Major Len W. Cox - Advertising Manager} K200 Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}20/KW.27.2.36. 4¼ Litre Bentley. Replying to your Cx.{Major Len W. Cox - Advertising Manager}14/KW.25.2.36. The figures you sent on the small blue print, and which we now return, are quite accurate figures taken on our 1-B-IV car. Unfortunately, neither of the two cylinder heads tried on this car are production heads, which latter has a compression ratio of 6.6. We do not anticipate, however, that there will be a noticeable difference between the figures for the 6.8 head, which are the same as those sent in memo. Hs{Lord Ernest Hives - Chair}/FD.{Frank Dodd - Bodies}4/KW.7.1.36, and the production head. As regards petrol consumption, Mx.{John H Maddocks - Chief Proving Officer} has done a few tests which show that when driven at the same average speed the large bore engine has a slightly better petrol consumption than the 3½ litre. We anticipate that if both cars were driven to the limit, the 4¼ litre would use more petrol than the 3½, but have not yet obtained any figures under these conditions. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} Att: 1 blue print. | ||