Mazda's engineers worked overtime to keep the third-generation MX-5 from gaining performance-dulling weight, and it shows. Liberal use of lightweight and high tensile metals, along with fresh thinking in such basics as mounting accessories to the engine and even how much a rearview mirror weighs, kept weight to within 22 pounds of the the second-generation Miata. Dropping the spare tire helped, but the MX-5's designated dieticians still faced added calories from the larger engine, the head-and-thorax side-impact airbags, more robust side-impact hardware, larger wheels and those stylish seatback hoops.
Just as significant from the driver's seat is how the car's mass is distributed. The lower the mass is in the car's chassis, the lower the car's center of gravity and the more stable its ride and handling. But especially important for a sports car, the closer weight is clustered around what engineers call the vertical yaw axis the better. Imagine a broomstick with two five-pound weights attached. It weighs about 10 pounds regardless of where the weights are positioned. Put the weights at the ends of the broomstick, and try to spin it like a baton. It's not so easy to get started, and once started it's difficult to stop. But move the weights next to each other at the center of the broomstick, and starting it spinning and stopping it requires much less effort.
This is a simplification because concentrating too much of the mass around the yaw axis can make a car unstable, but you get the point. And so did the Mazda engineers. The engine in this latest version was moved rearward more than five inches from its relative location in the previous (pre-2006) model. The gas tank was moved forward and lowered in the chassis. Relocating the battery from the trunk to under the hood positioned it closer to the yaw axis.
What all this has accomplished in pursuit of the ideal 50/50 front/rear weight balance is, well, if not perfection, then close, depending on how the Miata is loaded. With two people buckled in, Mazda pegs the new Miata's weight distribution at 50/50. With their luggage, it tends to a rear bias; empty, with a full gas tank, it tends to a front bias.
So much for what gratifies the left brain. What's so cool about all this shifting around of mechanicals and components is, it works.
The MX-5 is a blast to drive. The 166-hp, six-speed gearbox and a highly responsive throttle give it a nice kick in the back end. The wide track and low center of gravity enable it to corner flatter than should be possible. Balance is so close to perfect, with two people on board, of course, and with the sporty, asymmetrical-tread tires on the Sport and Grand Touring models, that it holds its line through corners like it was highway striping paint.
Quick, left-right-left transitions on a winding two-lane running along a bluff overlooking the Pacific Ocean on the Big Island of Hawaii succumb to nearly perfect steering response: light but not twitchy, with good feel regardless of the speed. Crank in more steering to keep it off the rock wall on the outside of a tight switchback, and the rear tires step tentatively sideways. A touch of counter steer and a soft feathering of the gas and the tires stick again, and away you go. What a rush. This is with the electronic stability control deactivated. With it active, the new Miata's still fun, just not as much.
We didn't have the opportunity to drive any models with the 16-inch wheels and standard tires and five-speed manual, but from experience with last year's Miata, we'd expect a similar experience, albeit at lower thresholds.
The new Miata cruises well, too, though on the Interstate it wanders slightly in response to pavement irregularities or when passing a heaving semi. When it must, the MX-5 can crawl along with stop-and-go traffic with no complaint. Clutch effort is so light, your left leg never gets tired.