Creating a strong passenger cell

The high X-bone frame is only part of the story, however. The side sills have been made particularly deep and connect with the front frame rails at the same point as the front legs of the centre tunnel. And running back from this same point is a straight, central floor member which connects front and rear frame rails. This 'three point support structure' where the sill, frame rail, floor member and central tunnel all meet, is very efficient at distributing load. Together with the deep side sills, it makes the body extremely resistant to deformation to create a strong passenger cell.

In the event of an offset frontal collision, the high X-bone frame does not twist upon impact. Instead impact load is shared evenly between the central tunnel, which absorbs around 40 per cent of the energy, and the side sills and central floor element. Furthermore, the front side members are completely straight and constructed in high tensile steel (as indeed are the rear side members) to make them particularly effective at absorbing energy. Running across the centre of the passenger cabin is a sturdy middle cross-member which is designed to direct crash energy into the centre tunnel in the event of a major side impact.

The overall effect of this innovative design is therefore a structure that eliminates shakes and vibrations, ensures pin-sharp handling and steering characteristics and conforms to worldwide safety criteria to provide outstanding occupant protection in the event of an accident.


Roll-over protection

A windscreen surround specially strengthened by a tubular brace and a pair of fully-trimmed roll hoops behind each seat with internal reinforcements and securely anchored to the high X-bone frame provide excellent occupant protection in the unlikely event of a roll-over accident.


Compact in-wheel suspension

HONDA S2000's suspension is a new generation 'in-wheel' double wishbone design with anti-roll bars front and rear, which although influenced by that of the NSX, differs in a number of critical details. Whereas the suspension of the NSX is largely aluminium, the HONDA S2000's is cast in steel, but because it is so compact, unsprung weight is kept to a minimum. Careful shaping of the components means that most of the structure can be located within the 16 in diameter wheels, to give packaging benefits; in particular, it helped the Honda design team in their quest for a low bonnet and rear deck line.

In-wheel suspension also provides greater rigidity by allowing the wishbones to be shorter and the upper and lower mounting points to be kept closer together; having a high stiffness to resist lateral forces improves the progressive, linear handling feel, the chassis' responsive nature, and general stability.

The front suspension employs a relatively low roll centre so enhancing steering feel and linearity by minimising suspension-jacking and track (width) changes as the vehicle corners or drives over uneven road surfaces. A low roll centre also helps keep the inner wheel closer to perpendicular (relative to the ground plane) during cornering.

The rear suspension features a wide based lower wishbone with a toe control arm for precise control (the NSX uses a toe control arm on the rear of the wishbone).

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