A four-door variant has once again joined the M3 stable, and in so doing makes BMW's raciest 3-series not only ergonomically more practical but also financially more palatable, with a base price that undercuts the coupe's by nearly $3000. Happily for bargain shoppers and kid schleppers, the extra doors have not dulled the sensations of this most sensational 3-series.

The biggest difference between the two body styles is that the four-door forgoes the coupe's carbon-fiber roof. So the four-door is heavier, but only by twenty-two pounds. That's not enough to affect the factory's 0-to-60-mph times - 4.7 seconds for both - and certainly not enough to alter this car's character. (And even as a sedan, the M3 is still lighter than its rivals from Audi, Mercedes-Benz, and Lexus.)

Although the M3 sedan can't match the carbon-fiber content of the M3 coupe, the siblings are identical in every other way. The sedan proffers the same visual treats, including deep air intakes, front fender gills, center-exiting exhaust, and eighteen-inch wheels. Inside, there are the same front sport seats with adjustable side bolsters, the fat-rimmed steering wheel, the M-specific trim, and the console-mounted Sport button (it quickens throttle response and reduces steering boost). The optional EDC (electronic damper control) adds another button to control the three-position electronic dampers. The technology package ($3250) includes navigation; EDC; a third, hypersensitive throttle program to the Sport button; and an intermediate dynamic mode to the stability control. The tech package also allows you to call up your favorite combination of the above with its steering-wheel-mounted M Drive button.

Our low-option test car, however, came sans technology package, navigation, adjustable dampers, leather, or even a sunroof. How old-school. But the important hardware was there - the completely M3-specific aluminum suspension, the stiffened body structure, the bigger brakes, and of course, the 4.0-liter V-8 engine.

Lurking under the suggestively bulging hood, the V-8 makes a robust414 hp, but it's actually lighter and more rev-happy than the previous M3's 3.2-liter straight six, reaching its power peak at 8300 rpm, just shy of its 8400-rpm redline. "Our way is to use a high-revving engine," says M3 technical director Bernd Limmer, "which allows us to use a light drivetrain." It also gives the M3 sedan a persona that is the polar opposite of a ground-pounding torque monster like the Mercedes-Benz C63 AMG.

The highest-revving four-door you can buy, the M3 is sure to elicit screams of fear and/or delight (depending on the temperament of your passengers) when you wind up its engine to the far reaches of the tach and the scenery starts coming at you like a sucker punch. The M3 was a fantastic partner for a long blast down the endlessly curving and blessedly empty Carmel Valley Road. Oh, and it's also a serene highway cruiser and perfectly polished in town. We didn't miss the whipsaw throttle option, but the available EDC would have mellowed the ride, which could be pretty stiff and jiggly. And were we able to put the DSC into dynamic mode, we could have hung the tail out in relative safety, putting an exclamation point on this car's beautifully balanced chassis. Still, even without all that, the M3 is one sensational car, two doors or four.

Open M3
The third model in the M3 family is the M3 convertible, which was unveiled at the Geneva auto show. Like the 3-series convertible, it has a retractable metal hard top. When it goes on sale in the States this summer, the convertible will usher in the M3's new seven-speed dual-clutch automatic, which BMW is calling M DCT Drivelogic. This transmission replaces the much-despised SMG gearbox and will spread to the M3 sedan and coupe shortly after its debut in the droptop.