Saturday, April 12, 2008

Automobile Review: 2004 Mazda Mazdaspeed MX-5 Miata

I've owned my proper sports car for almost 2 months now, so I believe I can give an informed opinion concerning its virtues and vices. I certainly have more experience with it than I did with the Mustang when I reviewed it. So, here's what I think about both the superficial and the substantial aspects of my little Mia.

What I like:
  • Exterior design. In terms of sheet metal, the 2004 Mazdaspeed Miata is the face-lifted NB body style, which dates from 2001, with front and rear air dams and a spoiler stuck on. The NB itself differs only slightly from the NA body style, which in turn dates back to 1989. In other words, the MSM's styling was 15 years old when it hit the market and is 19 years old now. Still, I quite like it. In fact, the face-lifted NB (NB-F) is my favorite Miata body style. I've been seeing a lot of NC Miatas since I've been hanging out on the Miata boards,and their angular, flared-fender styling has certainly grown on me, but I still prefer the swoopier NB-F with all its inflection points. This may sound like a ridiculous comparison, but I think my car looks like a baby first- or second-generation Dodge Viper. Like the Viper, the MSM is very curvaceous, with a slightly bulging bonnet* and squinty-eyed headlights, but the cabin and wheels are disproportionately large (like a puppy's feet or a human baby's head), the bonnet is shorter, and the expression is not so much mean as happy. Oh, and the car is much, much smaller. My favorite details of the bodywork are the aforementioned headlights, the subtly creased bonnet bulge (which is difficult to photograph), and the 2 ripples along the lower sides of car.
  • Wheel design. I disagree with Mazda's choice of wheel and tire size, but the wheel style, finish, and construction are quite nice. First of all, at 17.1 pounds each, the wheels are fairly light for their 17x7 size. There are certainly lighter wheels available in those dimensions, but those wheels are quite pricey, so I can't really fault Mazda for not putting them their inexpensive roadster. Secondly the style is quite functional and attractive. Thirdly, the finish is polished, but not chromed, so the wheels are attractive without being flashy and obnoxious.
  • Interior design. The interior of the car is attractively designed. I especially enjoy the red-stitched, black-leather bits and the red inserts on the doors and seats. Additionally, all the controls are within easy reach. The cockpit is not what I'd call roomy, but Alison and I fit comfortably. Of course, we are small people. The only nit I have to pick with the interior concerns the steering wheel. It's about an inch too large in diameter. A smaller wheel would effectively give a faster steering ratio, and the loss of leverage would be mitigated by the power steering. Plus, the wheel just looks too large on a car where everything is size XS.
  • Convertible top. I didn't really want a convertible when I bought the car, but I'm really enjoying having it now. I feel as if I've been imprisoned when I must drive with the top up. I guess my feeling on this topic must be obvious from all the top-down, hat-wearing, heat-on driving I did in February and March. The top is easy to operate; I can put it down in about 10 seconds and bring it back up in about 15. I've been impressed with the weatherproofing, too. It doesn't leak a drop, even in a downpour.
  • Stereo. The stereo, with its in-dash 6-disc changer and 6 speakers, is a solid performer. I'm no audiophile, but it sounds good to me.
  • Size. In my mind, a sports car should be small and light. I'm a big believer in Colin Chapman's command to "simplify, then add lightness." Thus, I'm quite pleased with the MSM's overall size. The weight---500 pounds more than my CRX---is greater than I'd like, due mostly to the convertible top and all the modern safety equipment.
  • Engine. The 1.8-liter, inline 4-cyclinder engine, turbocharged to about 8 PSI was the big draw to most MSM buyers. I was more interested in all the uprated suspension and drivetrain components, but I can't say that the I'm not enjoying the 178 horsepower and---more important---166 foot-pounds of torque that the mill puts it out.
  • Handling. The aforementioned suspension and drivetrain--by which I mean the limited-slip Torsen differential---don't disappoint. I can throw the car through the cones of an autocross course surprisingly quickly, but it also feels solidly planted at <mumble-mumble> MPH on the highway.
What I don't like:
  • Tacked-on "aero" bits. The MSM came with stuck- or bolted-on front and rear "air dams." I'm not sure how functional they are, and I don't dislike them, really, but they'd look much better if they weren't just tacked on. The NC takes a better approach; the Mazdaspeed front and rear air dams available for the third-generation MX-5 are integrated with the front and rear bumpers, so they look much better. The front actually looks like a much more functional piece, to boot. The Mazdaspeed spoiler for the NC is still stuck on, much like the one on my MSM, but it looks more integrated into the bodywork and also appears to be a much more effective design. The spoiler is, aesthetically, my least favorite feature of the car. Not only is it clearly an add-on, but, to my untrained eye, probably increases drag without adding any downforce---or reducing the net lift, to be precise. I've considered simply removing the spoiler, but that would leave 5 holes that would need to be filled, sanded, and painted to match the rest of the vehicle. It seems like I could add a more functional aftermarket part for a similar price. Thus, I've decided to table my spoiler plans for now. Besides, I'm sure there's more to be gained by cleaning up the underside of the car.
  • Power accessories. The car features a full suite of power options---windows, locks, and mirrors--- that I'd rather not have had to pay for. I'm even skeptical that the power steering is really necessary. And don't get me started on the failure rate of power accessories.
  • Fit and finish. Certainly, the car is a step nicer than my 17-year-old CRX, but it isn't up to the standards of 2004-era Hondas and Toyotas, especially on the inside. The eyeball vents are a particular source of frustration; two of them are almost too stiff to move, while a third is slightly loose and droopy. (With my new eyeball-removal knowledge, however I might be able to fix this particular problem.)
  • Convertible top. I've certainly been having fun with my top-down motoring, but I'm not certain the open-top fun outweighs the shortcomings associated with a ragtop. A convertible is heavier, less stiff, higher-drag, less roomy, and less durable than the corresponding hardtop. Also, I'll have to put a roll bar on the car to take it to a track; I wouldn't have to go through that expensive and time-consuming installation if the Miata were a hatchback.
  • Instrumentation. All Miatas come with 5 gauges: a large tachometer and speedometer surrounded by small fuel-level, oil-pressure, and coolant-temperature gauges. I can certainly understand that Mazda didn't fit the Mazdaspeed Miatas with a boost gauge, since fewer than 5500 copies were ever produced, and adding that gauge would have required reconfiguring the entire instrument binnacle. What I am irritated about is the misleading nature of the oil-pressure and water-temp gauges. They are, in fact, idiot lights masquerading as real gauges. The pressure gauge shows about two thirds of maximum if there is more than about 7 PSI of oil pressure and displays the minimum otherwise. In addition to saving Mazda a few bucks on each car, this setup apparently cuts down on customer complaints, since the needle doesn't fluctuate with engine speed. The temp gauge is similar; it shows the minimum when the engine is "cold," about half maximum when "warm," and somewhere near maximum when overheating. This simplified gauge saves a few dollars as well, but I doubt customer satisfaction was a motivation this time. Fortunately, there are procedures to fix these frustrating gauges; I'll report back if I implement them.
  • Underbody. The underside of the car is an aerodynamic nightmare, in terms of both drag and lift. The rear bumper, in particular, probably catches a lot of air and unloads the rear wheels. I can't really expect a car in the Miata's price range to have a complete and functional ground-effects kit including a splitter, Venturi ducts, and a diffuser. I don't think it's unreasonable, however, to ask for some simple paneling to reduce drag and therefor lift. Something like what's on my neighbor's Civic Hybrid would be effective and inexpensive.
  • Wheel and tire size. The 17x7-inch wheels that came on the Mazdaspeed Miata are simply too large and heavy for that car. The 2004 MSM's wheels weighed 17.1 pounds, and the 2005's wheels weighed a whopping 18.4. And all that weight is both unsprung and rotating, which is the worst kind of mass to add to a vehicle. 17-inch wheels might be acceptable, but only if they were among the lightest wheels available in that size, which would not be appropriate OEM hoops for a car in this price range. The MSM also came with extremely low-profile 205/40R17 tires. The low profile results in an outside diameter similar to that on the non-Mazdaspeed Miatas and yields good cornering, but also exposes the rims to potential damage from potholes and other surface discontinuities. The 215/40R17 tires I put on have just about the right amount of sidewall, but add 2 pounds of unsprung, rotating weight. The MSM should have come with reasonably light, reasonably priced 15- or 16-inchers with somewhat taller tires. I'm hoping to put on some very light 16x7-inch wheels and 215/40R16 tires when the current tires wear down. If I could find some 16x7.5s, that would be even better.
  • Transmission. The 6 forward speeds offered by the transmission are nice to have, but I still find the shifting to be more difficult than it should be. Additionally, the short gearing does enable very speedy acceleration, but it also means the engine is working harder at highway speeds than I would prefer. I would argue that first through fifth gears should be exactly as they are, but that sixth should be geared quite a bit taller, so that, at 60 MPH, the engine is running at 2500 RPM rather than 3000. If I do put on the smaller wheels and tires I mentioned above, or if I add any significant power, I'll probably change the final drive ratio from its current 4.1 or so to something like 3.9 or even 3.6; first gear will be close to useless if I don't.
In summary, this car is far from perfect, but I'm enjoying owning it quite a lot. The car is simply great fun to drive, through neighborhoods, on the highway, or in competition. Even after having this vehicle for 2 months, I'm still disappointed each time I arrive at my destination, because I won't get to drive any further. Overall, and considering the modest price, I give it 8.5 out of 10.

* I've been watching a lot of Top Gear lately, and I've decided to adopt some automotive Britishisms. Pretty soon, I'll be quoting naught-to-60 times and explaining that estates are even more practical than saloons, but that I really prefer coup├ęs or shooting brakes.


  1. "Also, I'll have to put a roll bar on the car to take it to a track..."

    Is there any way to actually roll a Miata on a flat surface? I suppose if you hit a jersey wall at high speed you might turn over...

    As for the undercarriage, there is a definite downside to adding a bunch of aerodynamic plates to it: labor charges. If the bottom of the car is covered with plates, then even a simple oil change becomes a major plate-removal operation. So, the plates make it more raceworthy at the expense of real-world practicality. Of course, with the Mazdaspeed model, it would seem that particular brand of trade-off has been made many a time, and that it wouldn't necessarily be so bad to make again.

  2. I certainly pushed the car past its limits during my autocross school---I even spun it about 180 degrees once---and rollover never seemed imminent. Still, I understand that the precautions for high-speed driving on a track are more stringent than for the slower driving one does on an autocross course laid on on a parking lot. Would my Miata roll if I hit a curb sideways at 75 MPH? Maybe.

    Incidentally, the "roll bars" you see on many convertibles are what are known as "style bars:" they are for show only.

    Your point about labor costs is a good one. But, like you say, perhaps the trade-off should be in a different place on a performance-oriented car. Also, the underbody paneling I've seen on some cars leaves a gap under the oil pan, so that the pan itself forms an aerodynamic surface more-or-less flush with the undertray, so the oil can be drained without removing any paneling. My own car is a bit like this, though the undertray in the front of the car represents a rather half-hearted effort. It's important to realize that the undertray doesn't have to be a completely smooth cover for the underside of the car; it can have gaps and surface texture due to mechanical components while still dramatically improving the coefficients of drag and lift.

  3. Anonymous10:46 PM

    Better just stick to Hondas brother. Clearly you are not any kind of real driving enthusiast and are too hung up on limitations you probably read about, spoilers causing SO much drag and losing SO much rigidity with a soft top, funny how this car's handling capabilities are compared with cars more than doubling its price. As a matter of fact I think at the time the Viper SRT10 was the only car with a better Slalom time. My suggestion would be spend less time bashing it and more time actually driving it, you might be surprised . Then again I could be wrong, and if you are such a good engineer that you can create a car more exhilarating for under 30 grand I'll be happy to trade in my keys.
    Jinba Ittai!

  4. You seem not to have read my review, which was, on the whole, positive. You also don't seem to have read my other posts on this car, or you'd see that I have put significant time behind the wheel---on the street, the autocross course, and the race track---as well as underneath it and in the engine bay. Given my experience with the vehicle and my PhD in engineering---admittedly electrical engineering, not mechanical---I feel entirely qualified to express my opinions on its virtues and vices.

  5. Anonymous9:11 PM

    It may lose some rigidity to the fact that it has a soft top, but even with this strike against it, there are very few better handling cars. It would seem to me that this is not even an issue worth mentioning. If it must be mentioned then it should be a positive note, designing a convertible that has the body stiffness, handling and suspension that is on par with cars costing 3 or 4 times as much.

  6. Certainly, it's good that the chassis isn't more noodly than it is, but the cowl shake and chassis flex are noticeable. My NC is markedly stiffer despite also being a convertible.