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 vibration and noise levels resulting from six different front suspension configurations on a Bentley.
| Identifier | ExFiles\Box 154a\4\ scan0103 | |
| Date | 15th March 1939 guessed | |
| - 2 - to this vibration, and partly to the drumming of body panels and chassis members caused by the initial shock transmitted to the body through the front suspension. It appeared therefore that the noise would be diminished if the longitudinal stiffness of the front suspension were reduced. Six different suspension conditions were compared to show the effect of different degrees of stiffness. (1) Normal Bentley 50 suspension (1.B.50) (2) As above, but with torque arm disconnected. (3) With torque arm and steering tubes disconnected. (4) Rubber damping between torque arm and frame. (5) As (1) but with no rubber damping on yoke. (6) Production Bentley 2 chassis, orthodox front wheel suspension. The figures given with a horizontal travel of the weight of 38" were :- | | Vibration amplitude Centre of windscreen. | Effect on sound amplitude. | |---|---|---| | (1) Normal | .04 to .045" | - | | (2) Torque arm off. | .02" | 35% decrease from (1). | | (3) Steering tubes off. | .02" | " " | | (4) Rubber under torque arm. | .03" | 30% decrease from (1). | | (5) No Rubber on yoke. | .045" decay rapid. | No decrease decay rapid. | | (6) Orthodox suspension. | .03" | 40% decrease. | The results obtained with the vibrograph on any one condition showed agreement within a range of 10% for six | ||