"We leveraged a great platform." That's how Bob Broderdorf, Jr., Fiat's North American director, summarizes the creation of the 124 Spider . We all know Fiat's new roadster shares its underpinnings with the fourth-generation Mazda MX-5 Miata , but there are a lot of key differences to keep them separate in the eyes of consumers. Mazda may have engineered the platform, but Fiat added many of its own touches.Here, we'll take a closer look at the spec sheets of the two cars, and summarize the major differences between the Japanese and Italian roadsters. If you need a refresher, read our full First Drive of the 2016 MX-5 Miata , and glance at all the Fiat 124 Spider details in this post Fiat Chrysler design lead Ralph Gilles is super excited about this car. "I think it's going to change lives," he told the assembled media at an event in Auburn Hills, MI, earlier this month. Yes, it's definitely exciting to add a small roadster to any lineup, especially one that uses such a proven platform. But we're not sure people are going to get all that jazzed about it from a design standpoint. You'll either love it or hate it, and we're kind of leaning toward the latter.Every single body panel is new, and the design is "100 percent Italian." There are a number of creases and angles throughout the exterior, with a squared-off rear end and rectangular taillamps. Fiat trusts you'll be able to spot the similarities between the new 124 Spider and the original, but we're not so sure. We can see a bit of the old car's grille on the new car's face, and the dual hood blisters are a nice throwback touch, but that's about it. Trust us when we say that this car looks way better in photos. In person, it really didn't wow us.Of course, beauty is in the eye of the beholder. One colleague told us his wife, a long-time Miata owner, hates the look of the new one but will absolutely adore the Fiat. Good for her, and good for Fiat. But based on design alone, we'll take the Mazda every single time.What about you?

Dimensions

Length Fiat: 159.6 inches Mazda: 154.1 inches

Width Fiat: 68.5 inches Mazda: 68.3 inches

Height ​ Fiat: 48.5 inches Mazda: 48.6 inches

Weight Fiat: 2,436 pounds (manual) / 2,476 pounds (automatic) Mazda: 2,332 pounds (manual) / 2,381 pounds (automatic)



Drivetrain

Power Fiat: 160 horsepower @ 5,500 rpm Mazda: 155 horsepower @ 6,000 rpm

Torque ​ Fiat: 184 pound-feet @ 2,500 rpm Mazda: 148 pound-feet @ 4,600 rpm

​ Power to Weight Fiat: 15.2:1 Mazda: 15.0:1



On The Road

Interior

Our Verdict

When Broderdorf said Fiat leveraged the Miata's platform, that means the Italians took it as-is. The two cars ride on an identical, 90.9-inch wheelbase. The front and rear tracks lengths are the same, at 58.9 and 59.1 inches, respectively. But that's where the similarities end.Yes, the 124 Spider is a full five and a half inches longer than the Mazda, and that's evident when you look at the cars in profile. While the Mazda's wheels are pushed out to the corners, the Fiat's overhangs are greatly exaggerated by comparison. Fiat says some of this was done to increase cargo capacity and make the small roadster as functional as possible. The Miata has 4.6 cubic feet of trunk volume, while the 124 has 4.9.Weight is the key difference between the two cars. In base spec, the 124 Spider is a full 104 pounds heavier than the Miata, though that gap shrinks to a 95-pound difference when comparing models equipped with the automatic transmission. Whether or not that weight penalty hurts the Fiat, though, we'll explore in the next section.One of FCA's engineers said the company "made the best tradeoff to make this a Fiat car ." A 100-pound weight penalty is a bummer in a car this size, but what's under the hood might make up for it. Mazda uses a naturally aspirated, 2.0-liter inline-four, but Fiat employs a turbocharged, 1.4-liter engine – the one from the 500 Abarth. That means there's more power on tap in the 124 Spider, and if our time in the scorpion-badged 500 is anything to go on, the 124 Spider should sound absolutely wonderful.As you can see from the numbers above, the Fiat has a healthy power advantage. That's especially true with the torque output – not only is the Fiat 36 lb-ft stronger than the Mazda, full thrust arrives much lower in the rev range. Still, look at those power-to-weight ratios. Comparing pounds per horsepower alone, the cars are seriously close, with the Miata barely edging out the Fiat (remember, in this spec, lower is better).Six-speed manual and automatic transmissions are available for both roadsters. Despite the different engines, the automatic transmission has the same individual gearing in both roadsters, though the final-drive ratios are different – Fiat's is 3.58, Mazda's is 3.45. As for the manual transmissions, Mazda's individual ratios are geared higher, as the naturally aspirated mill has a larger rev range. Fiat's 1.4-liter turbo-four cuts off at 6,250 rpm, while the Miata's 2.0-liter will spin to 6,800.Goes without saying, but we have no idea how the Fiat drives. The turbocharged engine will no doubt change the overall driving characteristics, as will the added weight on the chassis. We've praised the Miata over and over for being one of the best driver's cars ever built, with its light, communicative steering and excellent chassis tuning. Everything in the Miata is engineered around the driver, and since most of the mechanicals carry over, we don't expect that to be any different in the Fiat.Both roadsters use rear-wheel drive. At 15.5:1, the steering ratio is the same across the board. A double wishbone suspension resides up front, with a multi-link setup out back. A choice of 16- or 17-inch wheels is available, depending on model, and both the Fiat and Mazda's rollers are wrapped in the same tires. Standard brake types and sizes are exactly the same, too, though Mazda does offer an upgraded Brembo package on the Miata Club.Nowhere are the two cars more similar than inside the cabin. Look at the 124 Spider, then glance at the Miata, and you'll only notice very minor changes. Even by the numbers, dimensions for headroom, legroom, and hip room are the same. Only the shoulder room is ever-so-slightly different, the Mazda with 52.2 inches at the Fiat with 52.1.Fiat says it made a number of changes to the Mazda's interior, but they're not easy to see. The interior door panels are tweaked, there's an extra layer of soft-touch material on the dash (like, it's just added to the top of the existing Mazda plastic), and the instrument panel uses different fonts and colors that are better in line with the rest of Fiat's products. Even the infotainment system is a Mazda job, with everything controllable via the dial on the center console. Credit where it's due, though, Fiat does incorporate a thicker-rimmed, leather-wrapped steering wheel in the 124.After sitting in the two convertibles, we can't fault Fiat for keeping Mazda's work intact. For a small car, it's surprisingly spacious and comfortable. We love how easily you can flip the top back – that motion is just as smooth and simple in the 124 Spider. Would we like a little more differentiation between the two cars? Sure. But unless you've spent extensive time in the new Miata, you'd never know the 124 wasn't an original creation; it's all very cohesive.Look at it this way: Everyone who complained about the Miata not going turbo now have a reason to stop whining. And everyone who thought the Miata just wasn't, we don't know, funky enough now has a little Italian sports car with its own distinct style. Side by side, you won't know the two cars are the same (until you step inside).On the road is where these two cars will indeed differ. The Fiat's turbocharged power and (likely) better sound will be a treat, even with the 100-pound weight penalty. But unless the Fiat is drastically different (and better), we have to stand by the theory of "if it ain't broke, don't fix it." Still, we're stoked to drive the 124 Spider, and we can already see our proper comparison test brewing.