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 performance, consumption and axle ratios for a 4½ litre Bentley engine.
| Identifier | ExFiles\Box 82\4\ scan0244 | |
| Date | 10th February 1936 | |
| W/S - Cx.{Major Len W. Cox - Advertising Manager} c. to Bly.{B. W. Bleaney - Bentley Sales} x200 Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}7/KW.10.2.36. 4½ litre Bentley. Replying to your Cx.{Major Len W. Cox - Advertising Manager}3/ES.7.2.36, the 4½ litre engine at 3750 revs. on the unit test bed, gives 105 HP. when coupled to the present test bed exhaust system. This system has not yet been modified to suit the larger engine and throttles it unnecessarily. It is not therefore a fair figure for H.P. and if you like we can send you open exhaust figures for both the small and large engines. The horse power at the road wheels has not yet been obtained on the production dynamometer. With regard to petrol and oil consumptions, we have not yet obtained figures on the same car for the petrol consumption with the two engines. We do not expect the oil consumption to be any different from the small engine. As regards the higher axle ratio, the Works at present fit the 11/43 ratio for those customers who desire something higher than the standard 10/41. We have never fitted an 11/41 ratio to a customer's car, the intermediate 11/43 giving 100 m.p.h. at 4,500 revs., which incidentally is still the maximum permissible revs. of the engine, and not 4750 as mentioned in paragraph 3 of your memo. The Works say there will be no difficulty in supplying 11/43 axles if and when they are wanted. One of these axles was fitted to B-56-BN{W.O. Bentley / Mr Barrington} when in France. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||