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).
Performance and speed trial results of the Bentley Streamline Car.
| Identifier | ExFiles\Box 90\1\ Scan061 | |
| Date | 27th December 1933 | |
| W/S - Sr. from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}16/KW27.12.33. Bentley Streamline Car. Many thanks for your Sr4/MLG.22.12.33. We are very satisfied with the results. I had hoped to have got a timed speed of 100 m.p.h. over the kilometre, but since it was only possible to time the lap, the figure of 98 m.p.h. is all we can expect. We think that considering the weather conditions you did remarkably well. For the purpose of our records we should like a statement from the officials at Montlhery to say that the car was timed by their electrical apparatus, and that the speeds recorded were obtained, presumably they can do this even though you do not state compression ratio, etc. With regard to the engine revs recorded, we are not surprised that the streamline car did not exceed 4350 r.p.m. Actually the peak of the power curve is about at this point, and therefore we should not gain any maximum speed by fitting a lower axle ratio, and we should certainly over-rev under favourable conditions on the road, since in England we have had the speedometer round to 110, which means a true speed of about 103 m.p.h. The open car is of considerable interest to us, more especially are we intrigued by the fact that lowering the windscreen appeared to make 4 m.p.h. difference to the lap figure, a fact which we can scarcely credit. Therefore if you have an opportunity of repeating the test with the windscreen up and the windscreen down, it would be of interest to us. A thing which rather interests me is that the touring car with the windscreen up appeared to lap Montlhery at exactly the same speed as that which we obtained on Brooklands, i.e., 88.5 m.p.h. You will remember that I said that the streamline car was 8 m.p.h. faster than this, so that with the standard engine in the lap speed of the streamline car would be the same as we obtained on Brooklands, i.e., 95 m.p.h. The increased H.P. available appears to have increased the maximum speed by 3 m.p.h. I hope that you will get some business from this motor car. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||