Regressive valve assembly (Source: RE Suspension, Penske Racing Shocks)
The objective of the regressive valve is to produce a compression damping characteristic that allows increased low or mid-speed damping force or driver feel, while providing more suitable lower levels of high speed compression damping for bump absorption.
Spring washers can deflect in a linear, progressive, or regressive means and these devices show a symmetrical deflection around the washer's axis. Spring washers can be stacked to create spring sets or series where deflection and load capacity can vary without materially affecting the forces involved.
More linear damper characteristics imply that a vehicle responds in a more consistent way to road inputsspring progressivity affects vehicle roll and pitch angles during maneuvers and can change the lateral balance of the vehicle along the corner.
Composite coil springs (Source: Sardou S.A.)
Range Rover front air suspension module
BWI worked with tire maker Firestone to develop a new air sleeve for its air suspension modules. A nylon-reinforced rubber compound was developed that can handle extreme hot and cold climates. The changes helped improve the Range Rover's ride on rough roads. To provide the durability needed for off-road activities, the air sleeves are sheathed in an aluminum restraining guide. Weight was reduced through the increased use of aluminum in the system.
In the 70's - inspired by the Tyrrell 6 wheeler F1 car - there were a few 6 wheeled karts built.
Front suspension system
Each wheel had it's own springing medium, but shared a common anti-roll bar.
Including the bell-crank steering mechanism which operated both pairs of wheels from the single steering rack mounted on the front bulkhead.
A regular Formula One car behind the driver, but with a new front with double wheelpairs, where the front pair steered and the rear followed. The result was a car with 12 percent less wind resistance thanks to the small 10-inch front wheels. Four breaking front wheels would allow the drivers to break later than anyone else into curves and hairpins. More rubber on the asphalt would also bring better curve and breaking performance. In the rear they put on the biggest tyres available, mounted on 19 inch rims. The car was of course heavier, 590 kilos compared to the other cars 575.