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 steering characteristics and handling dynamics with comparisons to other car models.
| Identifier | ExFiles\Box 170\3\ img114 | |
| Date | 31th December 1936 guessed | |
| -2- Note from Chart I that one degree plus or minus at .4 g is a fairly representative figure. The direction of curvature of the steering angle line above .4 g is profoundly important. Downward curve means a rear skid and is dangerous. A sudden downward curve like the LaSalle and Olds 6, is due to too much rear stabilizer and is to be avoided. A uniform downward trend like the Terraplane and Chevrolet Standard is uniform oversteer and, while it makes for "snappy" handling, is bad in a side wind. The best curves on Chart I are the Chevrolet Master and Cadillac 60. This is not the whole tale however. These skid pad tests are essentially "static" tests. Transient conditions in steering are responsible for a lot of handling difficulties. For example on an independent suppose the wheels suddenly "flicker" a little bit, say 1/8 degree to the left. The c.g. of the car goes straight ahead. So the car rolls slightly to the right. The right hand roll of the front wheels introduces a "camber thrust" tending to balance the left hand steer effect of the front wheels. Hence the car does not turn. The sensation is of a disagreeable backlash in the steering. This is cured by a front stabilizer. It is not really cured but is reduced to a point where the backlash feeling becomes a sensation of "cushion" in the steering similar to that of fairly soft springs in the drag link. For this reason, of the above two cars, the Cadillac 60 really feels much better on the road. On skid pad draining. Ours has 9" conical dish to the center, so that zero acceleration occurs at 4 mph. If yours is generally flat I should drain it with small grids at the accidental low spots. Weather interferes with our skid pad work a lot. We are carrying our analysis of steering results a lot further than ever before by building up from them a series of curves of cornering power against load for various tire sizes and inflation pressures. These curves are similar to Figure 3 of R.{Sir Henry Royce} D.{John DeLooze - Company Secretary} Evans' SAE paper of 1935 on tire tests, taken from the Goodyear 8 foot steel drum. | ||