HONDA S2000 suspension system is well damped without being harsh, thanks to its Honda Progressive Valve (HPV) shock absorbers. These gas-pressure dampers use a stacked disc-valve arrangement that yields easily and progressively to high-velocity damper-piston movement, such as that created by bumps or road impact. However, when they encounter the slower movement typical of body motion, the disc valves offer more resistance and increase the damping force.

As well as being compact, the racing-style coaxial spring / damper units both front and rear offer low friction characteristics, while another motorsport-inspired feature at the rear is a separate gas reservoir which allows a bigger piston than could be accommodated in the body of the damper, to give a finer ride quality.

Honda also worked closely with Bridgestone in developing suitable tyres and the construction and rubber compound of the Expedia S02 tread pattern are specifically tailored for the HONDA S2000. The standard 16 in diameter, five-spoke, dished centre, alloy rims are shod with 205/55VR16 tyres at the front and 225/50VR16 tyres at the rear.


Limited-slip differential

An aluminium, torque-sensing limited-slip differential (LSD), which is currently used on a variety of Honda models including the NSX and Integra Type-R, plays a key role in the car's rewarding and progressive road manners. Elegantly simple and wholly mechanical, the design is both lighter and quieter in operation than alternative plate-type or viscous coupling LSDs, and features a multi-plate clutch and helical-type planetary gears.

In a straight line, the amount of slip between the rear wheels is controlled by a preset spring-loaded disc imparting a force on the multi-plate clutch. However, when differential wheel movement exists and these gears are thus forced to move, they develop an axial force, proportional to the drive torque, which increases the friction developed in the multi-plate clutch. The limited-slip effect therefore varies with the drive torque, which greatly enhances vehicle behaviour in difficult driving situations. In particular, acceleration out of tight low gear corners is improved by some 10 per cent because the tendency of the inner wheel to spin is reduced; and maximum acceleration on a 'split-mu' surface (grip one side, slippery the other) is typically doubled.


Latest-generation electric power steering

With just 2.25 turns lock-to-lock and a turning circle of 10.8 m, Honda opted to equip the new car with power steering to make short work of tight parking manoeuvres. It was also keen to provide the HONDA S2000 with a system that had a crisp, linear action, able to contribute to high speed handling and provide excellent road feel at high speeds.

A hydraulic power assisted system of course requires a pump driven off the engine which can sap power by as much as 5 PS as well as adversely affecting fuel economy. For these reasons, the HONDA S2000 is equipped with electric power steering (EPS) which only absorbs electrical energy when required. It is also more compact, weighs less and provides greater flexibility in programming steering feel at all speed ranges compared to traditional hydraulic systems. EPS is also more responsive at high speed and has been tuned on the HONDA S2000 to minimise kickback. The rubber coupling at the base of the steering column is particularly stiff so it damps unwanted inputs while retaining good road feel and informative feedback.

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