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).
Technical analysis of American car suspension, steering, and gearbox characteristics.
| Identifier | ExFiles\Box 173\4\ img214 | |
| Date | 5th November 1935 guessed | |
| (sheet 4) (though this latter explanation is denied by Olley). The Cadillacs, Buicks, and Chevrolets all roll from a point on the ground, the lateral translation produced by this low rolling point affecting the steering, so that it may be undesirable to reduce the height of our roll centre. Another advantage of the angular displacement of the wheels is the increased cornering power given to the front wheels by the reduction of camber on curves. It appears to be possible to control the steering joggles arising from the high roll centre, by attention to the steering box, and we have brought back a good deal of information as to Saginaw (who made the La{L. A. Archer} Salle Steering) and Gemmer.practice. As regards spring rates, Olley points out that the actual rate of semi-elliptic springs is also not constant, and that features of the mounting may affect the rate to a very considerable extent. These features are the length and angle of the spring shackle, the relative horizontal position of the eyes, the relation of the eyes to the top plate, and the camber. The most effective way to ascertain this actual rate, for both front and back, seems to be the method of mounting the four wheels on four weigh bridge platforms, and by means of jacks arranged to both push and pull, measure the deflection for any load by a pointer mounted rigidly across the frame and reading on an upright scale attached to the floor, at the horizontal distance of the wheels. Olley considers this the only reliable method of arriving at the actual rate. Referring to the Hudson suspension about which some interest has been expressed, even when fitted with a rear roll bar, the car is unstable in roll. In going from one track to another a self excited snaking can be set up which is very dangerous. There appears to be considerable roll bar effect from the front axle control, since Hudson's profess themselves unable to distinguish the difference between a front roll bar fitted, and none. The riding of the car with a full load was not bad, but not as good as Cadillacs. The torque arms were difficult to make strong enough, they said, seeming to indicate that there were some heavy uncalculated loads imposed. (4) As regards gearbox noise, actually American gearboxes * * | ||