Specifically, fewer, but more prominent horizontal bars fill the grilles of the 2006 models. The headlights look the same, but aren't; both beams are now xenon high-intensity discharge units. HID headlamps produce whiter light. Taillights fit in the same openings but now consist of LEDs, in place of last year's filament bulbs. Light-emitting diodes offer quicker response for the brake lights than traditional bulbs.
The bulging fenders and fastback and short front and rear overhangs give the Coupe its aggressive stance. This taut body layout, coupled with weight savings gained from a carbon fiber-reinforced, plastic driveshaft and an aluminum hood (and on the Roadster, a plastic trunk lid), balance the Z well for responsive handling.
The Coupe's sleek shape helps the Z slice through the air with a minimum of drag (0.29 Cd on the Track model). The Roadster's cut-off backlight (rear windscreen) isn't nearly as slippery (attaining a drag coefficient of 0.34 Cd). Underbody airflow is managed well, with zero lift on the front (and zero lift on the rear of the Track model).
