Bigger, faster, stronger, safer.

We expect to use those superlatives with almost every new vehicle — but when applying them to an icon like BMW AG's 3-Series, there's added scrutiny. For the world's benchmark sports sedan, does bigger, faster, stronger, safer necessarily mean better?

This is the dilemma faced by fabled makers such as BMW, Mercedes-Benz and Porsche AG when they launch a new generation of their beloved mainstays. While technical advances that deliver bigger, faster, blah, blah, blah usually are worthwhile, they often spoil the delicate man-machine interface that makes these cars so special.

It certainly happened in 2003, when BMW replaced the 5-Series, an excellent sport sedan that, despite its undeniable on-paper improvements, couldn't quite live up to the virtually perfect car it replaced.

With an arsenal of design improvements and electronic driving aids to deploy, BMW engineers prudently have honed them into an all-new '06 3-Series that manages to be technology laden, yet still intrinsically connected with the driver.

It couldn't have been an easy development process. A series of merely minor improvements would be out of character, yet anything that screwed up the industry's best sport sedan would throw the automotive world off its axis.

The '06 3-Series is the fifth generation of 3s and is internally designated E90. Wolfgang Epple, 3-Series program director, says every major component is totally new, and dimensions, as noted, are increased on nearly every plane. The 108.7-in. (276-cm) wheelbase is hiked by 1.4 ins. (3.5 cm); the new 3 also is 2.2 ins. (4.9 cm) longer and a not-insignificant 3 ins. (7.6 cm) wider. Epple says the new 3 is bigger because mankind gets bigger by an average of 1 mm (.03 in.) every year.

Oh, and the first warning bell: The E90 is heavier, as much as 130-plus lbs. (59 kg). Weight (and size) is not the friend of crisp handling.

To offset the inevitable weight gain, the new 3 has adopted, like the 5-Series before it, a front suspension and engine cradle chiseled almost entirely from aluminum.

More entertainment comes from the weight saving leveraged from the all-new engine family, code-named N52.

Don't worry, the hallowed inline 6-cyl. layout continues, but the N52 engine range is built with a new composite-metal construction technique that uses magnesium (25% lighter than aluminum) for the upper and lower crankcase, while aluminum comprises the structural core and cylinder bores.

The N52 3L DOHC I-6 weighs 22 lbs. (10 kg) less than the all-aluminum 3L I-6 it replaces, and is the first time, BMW says, such a design has been used in a contemporary automobile. Twenty-two pounds may not sound like much payoff, but the aluminum/magnesium engine block is one of the year's true showcase technologies.

The high-power version of the new 3L I-6 makes a no-nonsense 255 hp at 6,600 rpm and 220 lb.-ft. (298 Nm) of torque. That's 30 hp more than the standard-trim output of the “old” I-6 that, frankly, was being left like horse dung at the curb of the Fourth of July parade by its Japanese and European V-6 competitors.

The new lightweight marvel now makes a solid 85 hp/L, right up with the best 6-cyl. engines from Honda Motor Co. Ltd., Audi AG, Mercedes and Nissan Motor Co. Ltd. Better yet — as you might guess from the 6,600-rpm power peak — BMW engineers answer longstanding criticism of wastefully low redlines by extending the new 3L engines' limit to a sweet and satisfying 7,000 rpm. The wonderful new mills feel as if they would gladly crank on for at least another 1,000 rpm.

The lesser-endowed 3L engine's torque rating exposes these engines' single continuing problem: low torque output relative to like-size V-6s.

The new 3-Series inline 6-cyl. also now features the excellent Valvetronic variable valve lift system — which uses the intake valves to throttle the engine — first seen on BMW's vee engines. Efficiency is improved to boot, to a substantial 20/30 mpg city/highway (11.8-7.8L/100 km) for the 255-hp 6-cyl./manual transmission combo, for example.

There's hardly a high-tech box that cannot be checked off with these spectacular new engines, and performance is commensurately superb. Throttle response is even more spectacular than the high standard set by the outgoing M54 I-6 and there's the same refinement that's always made the straight-6 layout so smart.

Either engine is backed by a standard 6-speed manual transmission. The other currently available transmission option is the well-known 6-speed Steptronic automatic.

The new 3-Series suspension is subtly but meaningfully redesigned, too. Besides the move to aluminum construction, the strut front suspension is slightly revised with split lower control arms in place of the previous 1-piece arm. This “double-pivot” layout, which already suspends the front wheels of the 5-, 6- and 7-Series, is claimed to improve steering feel by limiting positive steering offset and create space for larger brake rotors and calipers.

At the rear, the new 3 adopts a 5-link independent setup that adds a new lateral track rod to the previous double A-arm arrangement. BMW makes a variety of performance claims for this new geometry, but our driving skills are too blunt to readily discern any handling improvement verses the old car's already high standard.

Combined with BMW's superbly biased and revised Dynamic Stability Control, the new suspension means one simply drives toward a corner, turns and the new 3 sticks. Then sticks some more until the G-force makes you sick. At the wonderful BeaveRun road course just outside Pittsburgh, you can make yourself hugely nauseous exploring the dynamic limits of the '06 3-Series. An interesting offshoot: all-new 3-Series cars ride on run-flat tires.

BMW's Active Steering system, launched a few years ago on the 5-Series, also is present for the first time on the 3-Series, although as an option.

We have deliberately delayed discussion of the styling because, well, you should best decide for yourself. This Bangle-era design, while the least shocking of controversial BMW design chief Chris Bangle's ministrations, also is the least provocative.

The sheet metal may not peg your personal aesthetic meter, but the interior certainly takes up the slack. There is surprising lushness and material density throughout the noticeably larger cabin. The sweeping door armrests verge on beautiful, the dashboard plastics are top tier and every button, knob and lever proffers the ultra-refined feel and operation we thought was forever cost-cut from this class of car.

BMW was stung by criticism for chintzy aspects of the 5-Series cabin, and the company may be compensating for those sins with the '06 3-Series.

But the fine trappings do come at a price. The 325i starts at $30,995 and the 330i begins at a lofty $36,995 — and even with the 330i, leather is not standard. A premium package is $2,900 and $2,200 for the respective models. BMW charges another $1,275 for an automatic.

Pricing may be dear, but BMW aficionados can let go any worries technology and refinement would ruin the brand's sharpest-driving car. Although a small degree of tactility may have been sacrificed to the electronic gods, BMW has engineered a host of changes without altering the 3's reputation for superior driving dynamics.

Apart from the sheetmetal, the 3 is not radically different from the car it supercedes — despite being almost completely redesigned. The new 3-Series is endowed with the changes necessary to stay contemporary, but BMW's stylists and engineers wisely have not let those improvements ruin the 3-Series' earned reputation as the world's foremost affordable luxury sport sedan.

'06 BMW 330i

Vehicle type: Front-engine, rear-wheel drive, 5-passenger 4-door sedan

Engine: 3L (2,996 cc) DOHC I-6, aluminum-magnesium block/aluminum head

Power (SAE net): 255 hp @ 6,600 rpm

Torque: 220 lb.-ft. (298 Nm) @ 2,750 rpm

Compression ratio: 10.7:1

Bore × stroke (mm): 85 × 88

Transmission: 6-speed manual

Wheelbase: 108.7 ins. (276 cm)

Overall length: 178.2 ins. (453 cm)

Overall width: 71.5 ins. (182 cm)

Overall height: 55.9 ins. (142 cm)

Curb weight: 3,417 lbs. (1,550 kg)

EPA fuel economy, city/highway (mpg): 20/30

Market competition: Acura TL; Audi A4; Cadillac CTS; Infiniti G35;Lexus IS 300; Mercedes-Benz C-Class; Volvo S40