The 2014 Infiniti Q50 is more than just an update of the old G - Series sedan.

There’s something a bit disconcerting lifting one’s hands off the steering wheel at freeway speeds, especially when your new Infiniti QX50 confidently maneuvers a high-speed curve without a moment’s hesitation – or drift.

With the launch of the new Q50, Infiniti is steering a new course – quite literally.  The new sedan, the replacement for the maker’s popular G series, is the first mass production automobile to use a steer-by-wire system, something Infiniti has dubbed Direct Adaptive Steering. But the sedan is also part of a figurative shift in direction by the Nissan luxury brand, after nearly a quarter century Infiniti now determined to move out of the second-tier ghetto to take on dominant luxury competitors like Mercedes-Benz, BMW and Lexus.

Part of the strategy to get there involves an all-new alphanumeric naming system.  Forget G, M, FX and JX.  Going forward, all Infiniti passenger cars will begin with a “Q,” while all crossovers and light trucks will be badged “QX.” The 2014 Infiniti Q50 is the first model to adopt that new nomenclature.

Of course, simply planting a new name on an old G35 wouldn’t be enough to make the big jump that Infiniti aims for. But the 2014 QX50 is a lot more than just a modest model refresh.

The Q50 is the first all-new Infiniti model to adopt the brand's new naming system.

For one thing, it introduces a raft of new technologies, most notably Infiniti’s new steer-by-wire system.  That’s part of parent Nissan’s “step-above” strategy, promising a level of refinement and features a notch above what one would normally expect in the entry-luxury segment.  And that, Infiniti hopes, will help it finally shift from an essentially U.S.-based, second-tier luxury brand into a truly serious global competitor.

New technology has become the price of admission in today’s luxury segment, but more traditional product differentiators still matter.  Like styling.  The 2014 Infiniti Q50 is a wee bit longer, a full two inches wider, and a half inch longer than the old G. Visually, that translates into a vehicle with a lower stance and a notably more dramatic and sporty presence, with a more distinctive grille, full LED lighting, more curvaceous silhouette and the now trademark reverse crescent curve to the C-pillar first seen on the Infiniti JX crossover – er, um, the rebadged QX60 which isn’t to be confused with the old QX56 that becomes the QX80.  Got it?

Nomenclature aside, the Q50 features a richly appointed cabin anchored by twin LED displays at the top of the center stack. The first serves traditional duties, such as navi. The lower touch screen operates various vehicle functions, including the promised upgrade of the Infiniti InTouch infotainment system. To our great relief, the maker has sidestepped the trap that sinks many competitors, providing not only redundant steering wheel and voice control but real switches and knobs for climate control and audio functions.

The new 2014 Infiniti Q50 is wider and lower, giving it a more muscular, aggressive stance than the old G.

The list of high-tech features is a long one and includes both familiar and new safety systems such as Nissan’s Around View Monitor, as well as Active Lane Control. The latter relies on a camera that scans the road looking for lane markers. It’s a step closer to true autonomous driving and it wouldn’t be possible without the optional new Direct Adaptive Steering technology.

Whatever one thinks of steer-by-wire, the Active Lane Control is almost uncanny in its ability to plant you in the middle of your lane and keep you there, even if the road is aggressively crowned. And it will even hold its position through modest curves – though Infiniti folks stress that this is not a hands-free driving system. And, indeed, you just need to give a slight nudge to the steering wheel before it relinquishes control.

For those unfamiliar with the steer-by-wire concept, it eliminates the normal mechanical link between driver and front wheels – though there is a redundant, clutch-operated mechanical back-up in case of a power failure. Having driven a rough Infiniti prototype in Japan a year ago, we were pleased with the production version’s overall feel which actually seemed a bit more natural than some of the electrically assisted mechanical steering systems we’ve driven of late – though performance-minded drivers are likely to remain wary. A nice touch is the ability to tune the level of steering boost.

Infiniti followed parent Nissan's "class-above" strategy by adopting a more refined interior than might be expected in the entry-lux segment.

All versions of the new Q50, in fact, allow you to switch between various modes, such as snow, comfort, sport and one in which you can mix and match according to your personal desires for such things as steering, throttle response, transmission shifting and suspension stiffness.

In the softer setting, the Q50 absorbed most of the harshness from the rough pavement we encountered during our drive through Northern New England, the trade-off was a less sporty response when you hammer the throttle. Switching to sport delivered the maximum pep the new Infiniti sedan is capable of but also meant a bit road harshness and even some juddering. The personal setting allowed us to opt for the middle ground on steering, for example, and soften up the suspension just a bit while still getting the boost out of the drivetrain we wanted.

Offered in both rear- and all-wheel-drive configurations, Q50 buyers will have a variety of powertrain options including a 328-hp 3.7-liter V-6, or a 354-hp hybrid that pairs a 3.5-liter V-6 with a 50-kW electric motor using a small lithium-ion battery for storing regenerated energy. A 2.2-liter turbodiesel rated at 170 PS will also be added for the European market though it wasn’t available for our drive. Both the gas engines are pleasantly quick, though Infiniti emphasizes performance as much as fuel economy with the Q50 Hybrid estimated to launch from 0 to 60 mph in 5.5 seconds, about four tenths faster than the 3.7-liter V-6.

The new 2014 Infiniti Q50 will be offered with a choice of either a 3.7-liter V-6 or a sporty hybrid drivetrain.

U.S. mileage estimates run as high as 29 mpg city, 36 highway and 31 Combined for the Hybrid, with the AWD 3.7-liter model cutting that to 19/27/22.

All-in-all, the 2014 Q50 is a worthy successor to the old Infiniti G sedan. It’s attractive, well-equipped and nicely appointed. It’s quick and most driver will likely check the fun-to-drive box. Traditionalists may be wary of the Adaptive Steering system and the dwindling list of true performance aficionados will likely lament the lack of a stick. But, on the whole, it’s a big step above the old G and, in many ways, other entry-lux competitors. It’s got a good chance of being noticed by those who never considered an Infiniti before.

(Oh, and for those waiting for the G Coupe and Convertible successors, hang tight. They’ll eventually reappear under the Q60 nameplate.)