It's about friggin' time.
For 14 years, everyone and their mother has been asking Mazda to pump a little muscle into the Miata. And for 14 years our pleas have gone unanswered. Look, it's not like we were asking for anything outrageous. It's not like we wanted a four-rotor stuffed between its shock towers. We just wanted the little roadster to be able to outrun a KIA Sephia when we asked it to. Well, Mazda has finally done it. And it's done it right. For 2004 you can buy a turbocharged Miata. It's called the Mazdaspeed MX-5 (Miata doesn't appear anywhere on the car), and it's exactly what you and your mother have been asking for. It's still not the fastest thing on the road, but only a fool or Big Daddy Don Garlits would call it underpowered. The engine is based on the same BP four-cylinder that continues to power normally aspirated Miata models.
Both engines displace 1.8 liters and feature double overhead cams, an iron block and an aluminum cylinder head, but don't think Mazda's white coats slapped a turbo on the sucker and called it "sake time." For starters, the variable intake cam timing system Mazda calls VVT isn't part of the package. Instead, Mazda went back to the pre-VVT cylinder head and camshafts of the 2000 Miata, which didn't have the VVT system. According to Kelvin Hiraishi, director of Mazda research and development, variable valve timing really isn't necessary when running boost, so the system was ousted to cut costs and improve the engine's midrange power. Mazda also modified the engine block to accommodate an oil line for the turbo, modified the combustion chambers slightly, and reshaped the pistons to lower the compression ratio from 10:1 to 9.5:1 and handle the extra fuel-air mixture provided by the turbocharger. Ah, the turbocharger. It isn't the Garrett unit used on the now-defunct Mazdaspeed Protege. Instead, it's a non-ball-bearing single-scroll unit from IHI making 8 psi of maximum boost at the manifold. Sitting in front of a larger radiator is a small air-to-air intercooler, which was chosen to keep excess weight off the nose of the car. The unit is visible through the car's lower grille opening, and may look too puny to do any good, but Mazda says careful fin design helped them achieve 75-percent cooling efficiency. Also, the oil cooler, which is positioned on the engine block, received two additional cooling plate pieces so the oil has more time to cool before it recycles through the engine.
Mazda rates the combination at 170 hp at 6000 rpm and 166 lb-ft of torque at 4500 rpm. On our Dynojet, our tester laid down 152 hp at 5800 rpm and 143 lb-ft of torque at 3700 rpm at the wheels, making it the absolute most powerful Miata Mazda has ever made. The last factory Miata we tested, a 2002 LS, spun the rollers with only 112 hp and 105 lb-ft of torque. According to Robert Davis, senior vice president of marketing and product development at Mazda, engine combinations making up to 250 hp were tested, but a nasty oil down on an L.A. freeway at that power level and the limitations of the Miata's chassis kept the engineers from turning the wick up too high. "We could have made a lot more power," says Hiraishi during a walk around the car at Mazda R&D in Irvine, Calif. "But it would overpower the chassis." Although the brakes went untouched, the six-speed transmission was made slightly stronger, thanks to shot-peened shafts and gears, and the clutch got a stronger pressure plate and a new disc. The differential is also new. Sort of. Mazda has gone back to the Bosch Torsen unit it used in the '99 Miata. You remember that car, don't you? We do. It was the best-handling Miata that's ever been.
Well, until now. Fact is, Mazda's engineers used the '99 Miata as the benchmark for all the dynamics of this car, which is why they quickened the steering, asked Bilstein to do the dampers, added larger front and rear anti-roll bars and lowered the car 10mm with shorter, stiffer springs. Well, they sort of lowered it. Once they bolted on the 17-inch lightweight Racing Hart wheels and Toyo Proxes R28 tires, which were specifically designed for this car, the car is really only 7mm lower, which is like the width of a pencil.
Mazda also put harder rubber in the engine and differential mounts, painted the brake calipers silver, smoked the headlamps, bolted on a unique front underspoiler with recessed fog lamps, glued on a rear spoiler and increased the size of the exhaust tip. Inside, there's red stitching on the leather shift knob, E-brake handle and steering wheel, and silver face gauges with the Mazdaspeed logo on the tach, which is but only one of nine times "Mazdaspeed" is labeled on the car. The name also appears on the decklid, the pedals, the scuff plates, the floor mats, the unusual body-colored rear-view mirror and the oil filler cap. All of which adds 89 pounds to the roadster's curb weight, which is now up to 2,529 pounds. It also has screwed up its 50/50 weight distribution, which is now in the 52/48 range. To which we ask, who the hell cares? We'll give up a tick or two of balance any day of the week if the tradeoff is nearly 43 hp and 44 lb-ft of torque.
On the road this car feels fast; it presses you into the seat and holds you there through all six gears. Short gearing makes it easy to keep the engine at full boil, but Mazda chose to regulate boost so it doesn't come on all at once and send novice drivers off the road backwards, and you can feel this in the power delivery. It's not really turbo lag, but you don't get that kick in the pants boostheads live for. Mazda's engineers told us they wanted the car to feel more like a Miata with a 2.5-liter normally aspirated engine than a turbo motor. And it does--torque is ramped up to its peak at 3700 rpm. Even in sixth gear at 70 mph, the engine is at the ready. That short gearing, however, along with the boost regulation and the car's newfound heft, don't really make numbers at the dragstrip. With a bit of wheelspin off the line and four, that's right, four gear changes, the best we got was 15.1 seconds at 90 mph. The car is geared so short, second gear only gets you to 48 mph, and you fly through the traps in fifth. The engine's redline, which has been lowered from 7000 rpm to 6500 rpm, also contributes to this.Because of heavy rains the week we had the car, we didn't get to test its handling on our favorite mountain road. Heck, we didn't even get to put the top down once, but there was just enough of a break in the weather to do our track testing at California Speedway. There, under threatening clouds, it snaked through our slalom at a very respectable 70.9 mph and circled the skidpad at .96 g.
Both performances blow away the numbers we recorded in the last Miata we tested, a 2002 LS, which managed 68.2 mph in the slalom and .93 g on the skidpad. And we're happy to report the car is just as tossable as any of its predecessors. It does understeer first, but a heavy right foot produces big, long powerslides, which we've never before been able to say about a Miata. Bilstein even managed to dial-in a livable highway ride, which is no small feat considering the two-seater's short 89.2-inch wheelbase. "We wanted the car to remain natural, balanced and easy to drive," says Davis during our little powwow at Mazda R&D. "Which is also one of the reasons we went with a turbo and not a supercharger. The engine with a supercharger was too torquey. The car felt like a 65-percent-scale Mustang convertible. Above all, we wanted the car to remain a Miata."
Mission accomplished. Whether it wears the name or not, Davis' car is the best-driving Miata ever. Four thousand units will be built and sold through 310 Mazdaspeed-approved Mazda dealers. It's available in two colors, titanium gray metallic or velocity red mica like our test car, and is priced to sell at $25,500 with the cloth seats, and $26,200 with the black leather, the only factory option available on the car. Now, Mr. Davis, about that four-rotor.
|2004 MAZDASPEED MX-5|
|Price as tested:||$26,200|
|Type:|| inline four, iron block,|
aluminum head, turbocharged
|Valvetrai:||DOHC, four valves per cylinder,|
|Bore x Stroke:||83.1mm x 85.1 mm|
|Claimed Crank Hp||178 @ 6000 rpm|
|Claimed Crank Torque:||166 @ 4500 rpm|
|Measured Wheel Hp:||152 @ 5800 rpm|
|Measured Wheel Torque:||143 @ 3700 rpm|
|Layout:||Front engine, rear-wheel drive|
|Curb Weight:||2,529 lbs.|
|Weight Distribution F/R:||52/48|
|Overall Length:||155.7 in.|
|Overall Width:||66 in.|
|Track F/R:||55.7 in./56.7 in.|
|Front:||Double wishbone, anti-roll bar|
|Rear:||Double wishbone, anti-roll bar|
|Front:||10.6-inch vented discs|
|Rear||10.9-inch solid discs|
|WHEELS AND TIRES|
|Wheels:||17-inch alloy Racing Hart|
|Tires||205/40R-17 Tyo Proxes R28|
|0-30 mph:||2.6 sec.|
|0-60 mph:||6.9 sec.|
|0-100 mph:||18.8 sec.|
|Quarter-Mile Time:||15.1 sec.|