2006 Infiniti M45

Momentum builds at Infiniti's upper range.

An unseasonable chill has descended upon the wineries and redwoods ofNorthern California. The winding, wooded roadways turn treacherous under a relentless, biting rain. It is, in other words, a perfect opportunity to test out Infiniti's newest offering, the M45.

It's been 15 years since the Japanese automaker made its auspicious entry into the American luxury market, a debut that conveniently coincided with Toyota 's launch of the Lexus luxury brand. Convenient for automotive observers, at least, for over the ensuing years, the two brands have been routinely compared and contrasted.

The results are stark and striking: Lexus today dominates the market, while Infiniti could be politely described as an automotive also-ran. Could the M45 change that equation? Infiniti certainly hopes so.

Half and half

First introduced in 2002, the M45 was something of a sleeper. It seemed designed to play counterpoint to the division's flagship sedan, the Q45, with plenty of power and a more sporty stance, but buyers weren't quite sure what to make of the M, whether it was a luxury sedan or a muscle car. And in today's crowded car market, there's little room for products that can't establish a clear identity.

With the launch of the new car, Infiniti isn't taking chances. It's given the 2006 M45 even more power, a decidedly more dynamic appearance. And at a time when the Q seems to be slowly fading away, this may be a perfect time for the new M to assume the flagship role.

The sedan comes from good stock, sharing its FM platform with the popular G35. The smaller model is the first Infiniti sedan to really gain traction in the U.S. market. It has established itself as sporty, nimble and quick, and its all-wheel-drive variant, the G35X, is proving especially powerful in the snow belt.

Infiniti claims 60 percent of the FM platform has been modified for the M45 and its V-6-powered sibling, the M35. It's been stretched a fair bit, for one thing. But it maintains the G's impressive torsional and lateral rigidity, a big improvement over the old M series. The new sedan's wheelbase is four inches longer than the old M45, and is now a full inch longer than the Q. Overall length, however, is down more than eight inches. When it comes to effective utilization of space, with the new M's wheels stretched all the way out to the corners, you'd likely never notice.

That confident stance is backed up with an impressive suspension package: a short and long-arm wishbone arrangement up front, with a multilink independent rear. Standard on the sport model is Infiniti's rear active steering. Unlike some earlier rear-steer systems, this is not meant to improve low-speed maneuvers or parking. It's solely there to improve handling, and while the amount of movement is modest - a mere one degree - it doesn't take much time behind the wheel on Napa Valley's treacherous curves to see how well the system works.

Of course, it also helps to have anti-lock brakes, traction control and vehicle dynamic control, all coming together to deliver a sweet ride.

Heart of the M

If the engine is the heart of a car, then in the M45, that heart beats strong and sure. The 4.5-liter V-8 is technically impressive, with four camshafts and 32 variably-timed Titanium valves. The engine makes a solid 335 horsepower and 340 lb-ft of torque. We'd like to have a manual gearbox to run it through, but it's hard to complain about the five-speed automatic, with its adaptive shift control.

In manual mode, the gearbox electronically blips the throttle to match engine and wheel speeds for faster shifts.

Squeeze the throttle and you're pushed back into your seat. Your ears share the pleasure, the exhaust bellowing out the sort of deep, throaty rumble you'd associate with a refined muscle car.

While the big engine is a pleasure to master, Infiniti expects to sell at least twice as many M35s, with the smaller but equally competent V-6. The six-banger pumps out a hefty 280 hp and 270 lb-ft, enough to launch the car from 0-60 in just 6.5 seconds.

That's as good as many competitive V-8s, and if you didn't know better, you might not realize which version of the new M you were driving.

There's actually one advantage to going for the six: like the G35, it's offered with an optional all-wheel-drive package. And we were impressed with its absolute sure-footedness during our drive through sopping wet wine country. Under ideal conditions, it splits torque 50/50 front-to-rear, but can put 100 percent of the power at either end, depending on conditions.

According to Infiniti General Manager Mark Igo, the division is carefully thinking over its AWD options, and we'd be pleased to see them offer this technology on the V-8 model sometime in the not-too-distant future.

Techno beat

There are plenty of other high-tech features available on the M45, either as optional or standard equipment, depending on the model. That includes adaptive lighting, which swings left and right as you steer, to help light your way into corners. Laser cruise control has become a must on top-line luxury cars. So has Bluetooth wireless technology meant to turn a cellphone into a handsfree phone. And the M45 features a reasonably easy-to-use, voice-controlled DVD navigation system.

But Infiniti is the first maker to market with Lane Departure Warning technology. The system uses a pair of cameras mounted in the outside mirrors. They constantly watch for lane markers, and if you inadvertently cross the line - or simply fail to use your signals - you'll get a gentle warning. We're a bit ambiguous about the concept, and will be curious to see how well the public accepts it.

The interior of the new M45 is sleek, comfortable and sophisticated. There's a theme running through many of the latest entries from Nissan Motor Co., starting with the Quest minivan, that has been adapted to the M45. Key controls are mounted, table-top style, above the center stack.

And the heart of the system is a multi-function control which Igo is quick to declare "less ambitious" than BMW's oft-maligned iDrive. For one thing, there are individual buttons that shift between such functions as radio, heat or navigation. The buttons are large, almost too large, but it makes things as easy to operate as any on the road right now.

The steering wheel has redundant controls for most critical operations, and it gives clear view of an elegant yet very functional gauge cluster.

Vibrant design

Inside and out, the M45 is the prototype of what Infiniti stylists have dubbed their "vibrant design" theme. Like the G35 before it, the new sedan is decidedly more distinctive than its predecessor, and has begun to create a clear and unique identity for the brand - without having to resort to gimmicks, like the original Q45's quirky belt-buckle grille ornament.

After spending a couple days in the new M, we expect it will draw the brand plenty of attention, building on the momentum provided by the smaller G35 and the edgy FX crossover vehicle. In fact, we would expect the M to seriously cannibalize sales from the fast-aging Q45.

There'd even been talk of the Q going away, with the M series assuming the role of Infiniti flagship. "Not so," insists Igo, though there appears to be a lot of debate over what to do with the next Q, with the replacement likely to try to move Infiniti more upmarket.

After 15 years, the brand finally has enough credentials - read: solid product - to justify such a strategy. Until recently, Infiniti was little more than an afterthought for luxury buyers and the M was just an asterisk on the sales charts. The new M is likely to fare significantly better, and justifiably so. It's handsome, fun-to-drive and technologically sophisticated.

2006 Infiniti M45

Base Price: $42,500 (est. M35); $49,500 (est. M45)

Engine: 4.5-liter V-8, 335 hp/340 lb-ft (M45); 3.5-liter V-6, 280 hp/270 lb-ft (M35)

Transmission: Five-speed automatic, rear- or all-wheel drive

Wheelbase: 114.2 in

Length x width x height: 192.6 in x 70.8 in x 59.4 in (50.0 in height for AWD M35)

Curb Weight: 3832 lb (M35 luxury) - 4004 lb (M35x AWD)

EPA (city/hwy): 17/23 mpg (M45), 18/25 mpg (M35), 17/24 mpg (M35x)

Safety features: Front and side dual-stage airbags, front and rear side curtain airbags, pre-tensioning seat belts, brake assist and electronic brake assist, ABS, traction and stability control

Major standard features: Driver and passenger power seats with memory, electronic alarm, cruise control, AM/FM/CD player, trip computer, leather seats, sunroof, power windows, mirrors and locks, Bluetooth for handsfree cellphone with voice recognition, auto climate control

Warranty: Four years/ 60,000 miles