The Mazda MX-5 convertible couldn't have shown up on a more opportune weekend — 80° temps in mid-October with Colorado's high country aflame with foliage. Although the scenery was breathtaking, Mazda's thirdgeneration roadster never wheezed once as it nimbly traversed winding switchbacks while effortlessly climbing multiple 10,000-ft mountain passes at over 70 mph (in sixth gear).

At the heart of the MX-5 is a responsive, MZR-Series 2.0-liter, 170-hp (at 6,700 rpm) powerplant that delivers 140 lb-ft of torque at 5,000 rpm. It features molybdenum-coated low-friction pistons and a high-compression ratio that reportedly boosts horsepower 20% over last year's model.

The '06 comes in five versions (Club Spec, MX-5, Touring, Sport, and Grand Touring) with three transmission options: five and six-speed manuals or a six-speed A/T automatic (Mazda's rendering of the shift-it-yourself slushbox). The six-speed manual tranny in the car I drove has especially short, tight throws that are not so close as to let you shift inadvertently into the wrong gear — well, maybe once while elbow driving and talking on the cell. Triple-cone synchronizers on the first four gears make for quick, smooth shifting on the open road as well as in hectic stopandgo city traffic.

The MX5's new light, compact engine uses cast-aluminum block, head, and oil pan, and is based on Mazda's A3, A5, and A6 models. It features chain-driven double overhead camshafts, four valves-per-cylinder, variable-intake valve timing to boost lowend torque and high-end power, electronically controlled fuel injection, and a coil-on-plug ignition. A complete redesign of the intake and exhaust reportedly drops intake restriction and exhaust pressure by nearly half.

The double wishbone front suspension coupled with a multilink setup in back improves chassis stability and handling. The rear suspension relies on gasfilled shocks to ensure tires stay in firm contact with the road — especially when cornering. Designers also moved the engine rearward 5.3 in. to reduce yaw inertia and get nearly a 50/50 frontto-rear weight distribution.

Some reviewers have been disappointed that the MX-5 didn't receive a more radical facelift. Instead, designers stayed true to the original, but did do away with the Coke-bottle-shaped body (as viewed from above). The car now has an oval aerial silhouette with narrower front and rear sections but wider in the middle for more hip, shoulder, and elbow room. Side surfaces are rounded with side skirts, tire-area deflectors, and front spoiler to control airflow under the body and along the sides to minimize drag.

Mazda reports that one of the most important aspects of the MX-5 redesign was managing the roadster's weight "gram by gram." The car weighs a mere 27 lb over the last model but is 1.8-in. longer, 1.6-in. wider, and 0.7-in. taller. Designers took every opportunity to shave weight including the use of aluminum in the engine block and hood, rear-brake calipers, frontsuspension control arms, and trunk lid. They also spec'd lightweight composite for intake manifold and camshaft covers and trimmed a fifth of a pound by redesigning the rear-view mirror.

Other amenities include stowage space, thanks to the addition of bottle holders in the door pockets, driver/passenger back panel storage boxes, a rear tray, and driver seat back pocket. A newly designed aero board also kept my hair from getting too terribly tangled with the top down. Located between the seat back hoops, the aero board slows down reverse-flow air that would otherwise rush back into the cockpit.

Our manual-tranny Sport version, featured a $500 option package with sport-tuned suspension, limited-slip differential, and Bilstein shocks, as well as a $560 delivery charge. This raised the sticker to just under 24K. The top-of-the-line Grand Touring version with black or tan cloth top (in place of vinyl) and sevenspeaker Bose sound system has a base sticker of about 25K.