Turbo tributes & tribulations

2007, Mazda, Speed3 GT

In case you haven't noticed, our transportation choices have become a bag of mixed greens. There are hybrids for the credulous; electric motors and fuel cells for the futurists; and diesels for the realists. Lost within this menu is "turbocharging." Once the preserve of hot-rodders hoping to goose more power from pint-sized powerplants, turbocharging has been undergoing a quiet evolution into an eco-option. The idea is that those same pint-sized powerplants can be made to feel like gallon-sized ones while improving efficiency and conserving fuel.

In principle, turbocharging is elegant and effective. The engine's exhaust pressure is used to power a small turbine that, in turn, compresses intake fuel-and-air for a bigger bang that then powers increased exhaust pressure, and so on and so forth. It's a virtuous cycle, and it really works.

Depending on your temperament, turbocharging may in fact work too well. Turbo motors are often nervous, skittish thoroughbreds. They're either off or on; at full stop or at full gallop. Turbo motoring is fun; but if you're not in a fun-loving mood, turbo-motoring won't meet you halfway. That's when "fun" begins to feel like a prickly pear in the pants. But you can at least console yourself with all the great fuel economy you're achieving.

If turbocharging is relatively unnoticed as a "green" technology, the MazdaSpeed3 is relatively unnoticed among turbocharged vehicles. Of the three models evaluated here, this super-sporty five-door wagon offers the best combination of performance, road manners and practicality. And it's the least expensive of the lot.

The secret lies with two simple considerations: power and weight. Mazda's 2.3-liter turbo inline-four uses a twin-cam design and variable valve timing to produce 263 horsepower and an astonishing 280 foot-pounds of torque. With a curb-weight almost 200 pounds lighter than the Saab 9-3 SportCombi or VW Jetta GLI, the MazdaSpeed3 is a rocket. Torque reaches its maximum at relatively higher rpms, but there's so much of it that skittishness is muted and turbo-lag while commuting is almost non-existant.

What's more, this Mazda sport wagon is fun to drive. The cockpit is driver-oriented and very European. It's a true five-seater, and the wagon design affords decent headroom for adults sitting in back. Cargo space of 16 cubic feet is analogous to that of a full-size sedan, yet it expands to about 30 cubes with rear seatbacks folded.

Six airbags and 18-inch wheels are standard, along with sporty bodywork, for a base price of $23,995. An optional nav system brings the as-tested price up to $26,300. But this is a car that's going places, so paying extra for navigation might well be worth it.

Here's the lowdown on Saab's 9-3 turbo sport-wagon, or SportCombi in Swedish: It's big and roomy. And heavy. And slow. Sometimes even scary, as you discover when you say, "Giddyup!" and ol' SportCombi decides to play "One-potato, two-potato" before deciding to get out of its own way. With this turbo-wagon, you need to plan your on-ramp accelerations with a Day-Timer.

The fault, and it is indeed a fault, lies with the 2.0-liter turbo-four. There are twin cams, but only 210 horsepower and 221 foot-pounds dedicated to bringing 3,320 pounds of car up to speed. Perhaps it's a lack of variable valve timing; but for whatever reason, turbo lag is frustratingly apparent. As a result, the 22 mpg/city, 30 mpg/highway fuel rating has all the allure of a false economy.

Inside, the SportCombi is roomiest and most versatile of the three turbos evaluated here. In addition to seating five, it will package cargo within an SUV-like range of from 30 to 72 cubic feet. Safety is a strong suit for Saab, of course, and ABS brakes and six airbags come standard. So do 16-inch wheels, which combine with Saab's distinctive, unusual styling to render the SportCombi's exterior rather eccentric. Base price is $27,495, which grows rather lofty after adding goodies like a moonroof, 17-inch wheels and others. Price as-tested then rises to $32,510. That's asking a lot, literally, for a vehicle that suggests tepid performance is more than offset by moderate improvements in fuel economy.

Volkswagen's Jetta GLI Fahrenheit is an exercise in flagrancy. There's the all-yellow-all-the-time paint scheme, for starters. And it isn't just restricted to the interior. There are chrome-yellow accents flecked throughout the interior of the Fahrenheit, as well.

And then there's the performance. But, wait a minute! Here's another 2.0-liter turbo, as in the Saab, but it only makes 200 hp and 207 foot-pounds of torque. And the Jetta's 25 pounds heavier than the SportCombi, to boot. But look: maximum torque appears at a low-low 1,800 rpm. And that means, when you tip the accelerator even a little bit, you're underway like a sprinter off the blocks. Where the Saab is glacial, the Fahrenheit is volcanic, hence, one must assume, the name.

Fuel economy is the best of the three reviewed here, at 25 mpg/city, 32 mpg/highway. Of course all three models require premium fuel, which is a hidden "turbo tax," so to speak. Jetta's interior is satisfyingly Teutonic, with a great layout for instruments and controls, and firm but comfortable seating. But in more ways than one, this unmellow yellow Fahrenheit is a kids' car. It's not just the paint-scheme. It's also the fact that the sloping rear roof line transforms any tall, rear-seated adult into Quasimodo. Of all three five-seaters described here, this one seems least versatile for hauling five grownups about town. Better, perhaps, to fold the rear seatbacks and expand the 16-cubic-foot trunk.

At $29,970, as-tested, the VW Fahrenheit slides in just under the magic "$30K" threshold. But that's still a whole lotta hard-earned green to ask for so much frisky yellow.

By Marc Stengel

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Images of the 2007, Mazda Speed3 GT

2007 MazdaSpeed3 GT front view
2007 MazdaSpeed3 GT front view
2007 MazdaSpeed3 GT rear shot
2007 MazdaSpeed3 GT rear shot
2007 Saab 9-3 2.0T SportCombi front view
2007 Saab 9-3 2.0T SportCombi front view
2007 Volkswagen Jetta GLI Fahrennheit front view
2007 Volkswagen Jetta GLI Fahrennheit front view