Lexus is trying to alter the image of the brand, or at least to add a modicum of 'sport' to what is a well-established reputation for building rock-solid, top-quality but boring vehicles.

As part of this exercise it has introduced a fourth-generation GS sedan for 2013 and made it available with an F-Sport package loaded with features developed specifically to enhance driving dynamics.

The rear-drive GS sedan was first introduced 10 years ago. The new-for-2013 GS has come in for a major redo with a new exterior design, new interior and a bit more power. It is available in RWD, AWD and hybrid versions. Our test vehicle was the RWD with the new F-Sport package.

The 2013 GS is the same size as the outgoing version but with the new style has a more planted stance. The length and wheelbase are the same but the new GS is five-cm wider. The chassis is 14 per cent stiffer and every panel and piece is new from the corporate spindle grill to the chromed exhaust outlets. The added width is also noticed, and appreciated inside.    

The interior is all new as well with higher quality materials and typical Lexus attention to detail, fit and finish. As has become the trend, brushed aluminum is used for trim instead of wood and glove-softleather abounds. Soft touch surfaces are in all the right places including where you might rest and arm or hand.

Getting comfortable should be a breeze for folks or any size or shape, The driver’s seat on my F-Sport-equipped tester featured 16-way adjustability while the front passenger had to make due with only 10-ways to adjust that seat. Combine that with a tilt-and telescope steering wheel andanyone can be made to feel at home.

The front sport seats have added bolstering to keep you in position when you check out the newfound driving dynamics. There is lots of headroom in front and a decent amount in back. Two will be comfy in the rear but three a squeeze, especially because of the tall center tunnel that carries the driveshaft – one of the penalties of rear-wheel drive.  

Obviously at this price point all the expected amenities are present. The F-Sport model comes with aluminum pedals with rubber inserts and perforated leather seating surfaces.  The instrument panel is a highlight thanks to its incredibly clear graphics andbacklighting.

As expected in this class a full array of amenities is standard as are dual-zone automatic climate control, a 12-speaker audio system and 18-in alloy wheels.

The $7,000 F-Sport Package included drive-mode select,variable steering, a unique steering wheel, four-wheel active steering, adaptive variable suspension, performance summer tires on unique 19-in alloy wheels, the aforementioned power seats and alloy pedals as well as plenty of F-Sport identification.

But you have to drive this car to fully appreciate thedifference the F-Sport package makes to the handling. This is the GS the way it should have been done in the first place. Select Sport S+ with the Drive Mode selector and be prepared to be impressed, and perhaps arrested. This position makes adjustments to the suspension, steering, stability control and throttle response, literally transforming this mild-mannered luxury car into a sports sedan, a serious sedan.

I had driven an early prototype two years ago in a heavily camouflaged guise and was impressed with the sharp response to steering input and almost total lack of body lean. But in the interim further tuning and tweaking has maintained if not improved these traits melding them with a comfy ride.

F-Sport-equipped models get adjustable shock absorbers, thicker anti-roll bars front and rear, a modicum of rear-wheel-steering, stiffer springs, different-size summer-only performance tires front and rear and a faster steering ratio.

The missing element, if there is one is the need for more power. The suspension and handling have been upgraded to the stage where they can handle a great deal more power. Perhaps that is to come in future upgrades.

Don’t be misled by that statement, the 3.5-litre V6 is a beaut with both direct and port injection and a healthy 306-horsepower and 277 lb. ft. of torque capable of propelling it to 100 km/hr from rest in less than six seconds.

Smooth and silent until prodded it emits a healthy but fake growl under WOT (Wide Open Throttle). I say false because the GS, like several other performance cars introduced in the past year, has a sound generating system in the air intake that funnels sound into an outletbehind the dash.

The six-speed automatic has been reprogrammed to snap off faster shifts under WOT and earlier lockup of the torque converter.

This is the GS that should have come along much earlier, capable of morphing from pussycat to tiger at the twist of a knob.

Specs

• Model: 2012 Lexus GS350 RWD F-Sport, 4-door, 5-passenger luxury car
• Price: $51,900 base, $61,035.20 as tested including freight and PDI
• Engine: 3.5-litre DOHC V6, 306-horsepower, 277 lb. ft. of torque
• Transmission: six-speed automatic, rear-wheel-drive
• Fuel economy: litres/100 km city/highway: N/A
• Length: 4,849 mm
• Width:  1,839 mm
• Wheelbase:  2,850 mm
• Weight: 1,721 kg