In place of the old car's 2.3-liter, the 2010 Mazda 3s receives the new 2.5-liter four-cylinder, first seen in the 2009 Mazda 6 sedan. Large four-pot engines tend to be rough and coarse, but not this one - Mazda's engineers did an astonishing job of quieting this long-stroke heavyweight by adding balance shafts and other refinement measures. There is no vibration to be felt at any engine speed, there's never any harshness, and with the windows down or the stereo playing, the engine is nearly inaudible. The old 2.3-liter was more vocal, and we miss its outgoing personality. But the larger engine's bite is likely more important to buyers than its bark. Peak output is up 11 hp to 167 horses, and a good chunk of the 2.5-liter's 168 lb-ft of peak torque is available throughout the rev range. The five-speed automatic transmission is optional again on the 3s, but the standard manual transmission now comes with six forward gears in place of last year's five-speed. The only option missing from our fully loaded, retina-searing celestial blue 3s Grand Touring test car was the automatic.
And when we say fully loaded, we mean fully loaded - this little charmer was equipped with luxury features you'd never expect to find in an economy sedan. Our candy-colored 3's youthful appearance seemed at odds with its decidedly grown-up arsenal of equipment: swiveling bixenon headlights, dual-zone automatic climate control, an eight-way power driver's seat with memory, a ten-speaker Bose Centerpoint sound system, a tilt/telescope steering wheel, heated seats, leather upholstery, keyless ignition, navigation with full iPod integration and Bluetooth, rain-sensing wipers, LED taillights, electroluminescent gauges, and . . . you get the point.
These features, some of which are not available in the Mazda's competitors for any price, could put the 3 on the shopping list of buyers looking to downsize from larger gas slurpers. Unfortunately, most of these luxury goodies aren't available with the more economical smaller engine, and even though the 2.5-liter's thirst for fuel is shot-glass petite in a Big Gulp SUV world, its 29-mpg highway economy figure barely exceeds that of the similarly sized BMW 328i, which has a much more powerful, 230-hp six-cylinder under the hood. Even the more efficient 2.0-liter's anticipated ratings can't match those of the Honda Civic and the Toyota Corolla, the 3's main competitors.