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Achieving the tightest possible bond between a driver and a sports car is feasible only if the vehicle responds in a linear, precise, and highly predictable manner. Mazda engineers invested deep soul searching on many field trips to agree upon Mazda MX-5's character and to identify how to best achieve this lofty goal through chassis tuning.

Two key words for the feeling they pursued were precise and nimble. The goal was for a natural, lively feeling instead of the cold efficiency of some well-oiled machines. While solid stability is essential for safe driving, the ideal for the new Mazda MX-5 was to develop a chassis that is keen to alter speed or direction as swiftly as the driver changes his mind.

Every aspect of driver control had to be coordinated with steering, suspension, brakes, engine, and transmission responses. How the driver's seat was configured, the distance to the steering wheel and shifter, the feeling of the brake pedal, the ability to heel and toe, all played a significant role in achieving the Jinba Ittai driving experience. The original MX-5 was quantified and higher targets of opportunity in all aspects were identified.

Crucial was developing a light but stiff unibody that serves as the chassis foundation. A double wishbone front suspension and multi-link rear suspension system with optimized geometry help extract the best the 205/45WR-17 radial tyres have to offer. Aluminium was used for some chassis parts to minimize unsprung weight. Attaching the rear cross member directly to the unibody with no rubber isolation enhances chassis rigidity while reinforcing the feeling of oneness. Careful tuning of the rack-and-pinion power steering gear yielded low friction, high linearity, and delightfully smooth steering response. The net stiffness of the path between the driver's hands and the tyre contact patches is increased. Another significant change is a 75 mm (3.0 inches) increase in front track and a 55 mm (2.1 inches) in rear track, which contribute to improved handling.

The newly-developed rear suspension is engineered to enhance dynamic stability by optimizing the positioning of the tyres on the road. To curb unwanted steering, pitch motion of the body during acceleration and braking is tightly controlled by the dampers and by anti-dive, anti-squat geometry. A wheelbase increased by 65 mm (2.6 inches) also helps balance the stable driving.

Configuring the braking system for short pedal travel, response keyed directly to pedal force and a high degree of linearity is also a means of enhancing the Mazda MX-5's feeling of oneness. Front rotors are 20 mm (0.8 inches) larger in diameter for improved thermal capacity and calipers are 25 percent stiffer. Brake hoses are less resilient and the power booster is 25.4 mm (1 inch) larger than before. Thanks to these revisions and improved front-to-rear balance, stopping distances achieved with the four-wheel single-piston-caliper disc system are exemplary.

Sixteen years of success with the original Mazda MX-5 established high expectations for its successor. Thanks to a deep respect for Jinba Ittai principles and thoughtful applications of Kansei Engineering, the all-new Mazda MX-5 is ready to convince sports car enthusiasts that a new triple-zoom era has begun. The all-new MX-5, after making its global debut at the 2005 Geneva Auto Show, is scheduled go on sale in global markets starting in the second half of calendar year 2005. Zoom-Zoom.

To be continued ...