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).
Analysis of the 15-EX steering system's characteristics and performance in response to feedback about it being 'spongy'.
| Identifier | Morton\M10\ img041 | |
| Date | 30th March 1928 | |
| 15-EX STEERING. Reference is made in Mr. Ghrylls note to the steering being spongy. Apparently, because the steering is known to be lower geared, it is assumed to be spongy. Actually, the overall ratio has been altered from 13-1 standard to 15-1 sports, at the same time the steering tube springs have had their rating increased from 1500 lbs/1" to 2000lbs/1", i.e., the ratio has been dropped 15% but the flexibility in the system reduced 30% so that the steering may definitely be said to be less spongy than that of the standard car. Personally, I consider that as we left the steering on March the 2nd, it was the best for high speed work of any car we have had in France. This, after 20,000/30,000 actual driving on these tests, due in a measure to the car springing and low build which have a considerable bearing on the problem. It was not a perfect steering, but the car was driven at 90 m.p.h. on a highly cambered road with one hand only on the wheel as a test of controlability; its behaviour was considered satisfactory under this somewhat exacting test. Below 70 m.p.h. we consider that the steering was as far as the art of making steerings has so far progressed, practically perfect. We know it was the safest steering in an emergency we have ever produced, because owing to the front axle control, it was unaffected by brake application. We know that there are factors which can alter the steering. If Mr. Ghrylls'statement contd :- | ||