F is to Lexus what AMG is to Benz and M to BMW. But is it fair to view the GS-F, a hot-rodded rear-drive medium sedan with tons of sporting spirit, as a rival for the E63 and M5?

For: Surprising agility given its size and weight, characterful drivetrain, well-equipped.

Against: Demands multi-mode dampers, conservative Sport-Plus and Track calibrations, time to start again with infotainment interface.

Score: 3.8/5

RACE track, road car: Sometimes it works … sometimes it doesn’t.

In respect to the Lexus GS-F, introduction by way of a couple of fast laps of Manfeild circuit on the eve of the biggest domestic motor-racing meeting on the national calendar, the New Zealand Grand Prix staged on the first weekend of February, was an interesting concept.

Taking this big sedan onto a track still cooling off from the shakedown efforts of Toyota Racing Series single seaters that in 48 hours would be contesting the top trumps prize our country offers the best driving talent wasn’t out of place.

Yes, Lexus means luxury and the GS-F, despite being the sportiest of its breed, maintains no shortage of that; more obviously than you’ll see in AMG, M-Sport or Audi RS product. But Lexus ‘F’ also means performance … and plenty of it in this instance. A 5.0-litre V8 that can power the rear wheels into tyre-smoking oblivion certainly enlivens a car that, in more modest format, is more attuned to pipe and slippers operation.

So, anyway, the laps: In the hands of a tame professional driver (this being a race weekend, the track rules meant only racing license holders allowed) the GS-F presented intrigue, it was clearly fast, but just short of furious; polished but perhaps not wholly playful.

So much of what it offered seemed to be summarized by the soundtrack. There’s a ton of V8 snarl here but how much of it is heard depends on where you happen to be.

Lexus credo that puts refinement and manners above all else doesn’t escape its performance models; but the clever acoustic management that makes it sound most impressively racy from within does seem to be more evident here than in the F division’s three previous offers - the discontinued IS F compact sedan and LF A supercar and the current RC F compact coupe.

From the outside, even at full noise, it’s a different car from within. Had this been an AMG, you would have heard it from the venue perimeter. Being a Lexus, it was barely audible as it thumped past the pit wall.

Was this episode a summary of all that this car is … and isn’t? Is this the reason the model pitches in at $174,900, well below the Audi RS6 and S6 and BMW M5 that might be considered competitors?

Those thoughts remained in my mind when this road test was conducted subsequently.

Style, specification

Four years have passed since the GS entered production but time has largely stood still for this car’s shape; there’s still no whiff of it having reached any particular use-by date. It has a rakishness and poise that pleases from any angle.

All the same, there’s no argument that the F-Sport enhancements make it all the more meaningful. And just plain meaner-looking. The whole idea of making this model appeal as a RC-F coupe but with two more doors and a proper back seat plays well. Indeed, even though a physically larger product than the two-door alternate, it looks better proportioned. An immediate impression is that the brand’s spindle grille looks better on this product that any other in the Lexus portfolio.

Brand contention that Lexus is the best that Japan can offer the world does seem slightly undermined when it has chosen French Michelin Pilot Super Sports, 19-inch BBS rims and Sachs dampers (from Germany) and Italian Brembo brakes.

Ingredients that some would argue makes the GS-F something of a multicultural parts-bin special are here for more than just show, obviously, though they also definitely enhance the visual appeal, as does the lowered ride height and employment of lip and boot aero spoilers. Both rendered in carbon fibre, of course.

Evidence of the quality that Lexus is renowned for shows in the precision of the car’s panel fit and flawless quality of its paintwork, but really hammers home when you enter a cabin that is immaculately finished and indulgently specified.

The employment of carbon fibre and alloy fillets, a chubbier steering wheel, F-Sport instrumentation and one-piece front seats sculpted to look like race chairs – though, of course, they are much wider and have full electric adjustment – ensures the F has more of a sporting air with than the lesser GS models, even though the basic interior design is otherwise much of a muchness, with the same pluses and frustrations.

It remains disappointing that a brand that achieves so brilliantly in the fundamentals of good design still falls down on the ergonomic details. The potential of that huge 12.3-inch infotainment screen at the head of the centre stack is largely undone by access being controlled not by touch but instead by controller on the centre console.

This unintuitive system that adjusts an often cursed cursor to access functions is the best example of how doggedly this brand seems to want to persevere with a set-up that simply does not work well unless you are parked up (the only time when the sat nav and Bluetooth functionality is fully freed up).

The plethora of buttons and displays makes the GS-F seem more complex than it needs to be. The provision of information sources is appreciated but almost overdone; there are many functions to scroll through on the digital instrument display, which also changes depending what drive mode you are in.

No knocking, though, the generosity of the overall specification. The provision of one of the most expensive stereo systems outside of super-luxurydom, a 17-speaker Mark Levinson stereo, says so much about this brand’s eagerness to go the extra mile.

The ‘F’ badge doesn’t stand for ‘family’ but nonetheless this model is the best of that breed to accommodate more than a driver and front seat passenger – to a point, at least.

Ultimately those chunky front seats restrict rear legroom as much as the sunroof reduces headroom, while the wide centre tunnel makes it more comfortable as a four- rather than a five-seater, yet with plenty of cabin storage and 520 litres of boot space, it at least offers opportunity.

Power, performance

Even though it is the most powerful engine ever fitted to a Lexus sedan, the 351kW and 530Nm 5.0-litre V8 here might seem both a touch old-school and lightweight compared to the latest competitor powerplants out of those rival brands. Turbocharged eights and sixes are the norm for Germany’s executive expresses these days and most are more walloping than the Lexus unit.

Yet it pays not to dismiss the Japanese effort. While forced induction is not a consideration for Lexus, it has hardly stuck to outdated methods. In addition to being quad cam and dual injection, it appeals to the techo-minded by having the choice of both more economical Atkinson cycle and Otto combustion cycles.

While you don’t get the sheering thumping kinghit of, say, an M5 or RS unit, this engine does provide an immediate appeal of sweetness and immediacy in its responsiveness; it also feels deliciously ‘natural’ in throttle application. It also demands to be worked - note that peak torque doesn’t come on until 4800rpm and that top power only produces at 7100rpm (just 200rpm short of the redline) but doesn’t feel any the worse for it.

All the same, the punch does deliver, at least initially, in slightly subdued manner. Even though the eight-speed automatic is impressively snappy, not least when used in its manual mode – accessed via either the tipshifter or steering wheel paddles – there’s a reality reflected in the claimed 0-100kmh time of 4.6 seconds, which is merely average for the price these days and, in fact, feels a tad optimistic from my experience. Also hard to hit is the claimed optimum fuel economy of 11.3 litres per 100km.

Driving

Potentially one good reason why the GS-F doesn’t feel as though it’s entirely pulling its weight in a straight line sprint is that it is hauling quite a lot of weight: A hefty 1850kg dry means it is a two-tonne (plus) mamma when fuelled up and loaded.

This has effect on kapow and also on the transmission’s action – in even Sports Plus, the most aggressive of four drivetrain-affecting mode, when it is left to its own devices, the box is prone to drop revs too quickly to the detriment of response – yet it doesn’t seem to impinge too heavily on the dynamic side. This is where this car acquits well, at least in respect to the handling side of thing, not least in that same Sport Plus setting.

Of course, fettling the drivetrain reaction is just one of the options. The GS-F also picks up the RC-F’s trick torque vectoring differential, whose Standard, Track and Slalom modes are designed to juggle drive between each rear wheel in different ways.

Also, when Sport S Plus is engaged, a VDIM Expert mode can also be employed as a stability control mode with severely reduced intervention; not quite to the point where you’re going to emulate Ken Block because, as is the Lexus way, it seems even ‘extreme’ is rather more tempered by the electronic aides than would be the case in some other product.

Even so, the car’s behavior on what you’d call challenging roads is surprisingy good; reminding why it felt so neat and precise – even when experienced from the front passenger seat – during that track work.

It feels much more poised and grippy than the standard car; while the steering could do with more feel, tplenty of front end bite when you turn-in and even body roll is less of an issue than you’d expect.

Those Brembos do get a work out, though, and the tyres, too: I wonder what the wear rate will be like, though while they are in good condition the stickability from those Michelins is simply brilliant. Overall, it fact, this car has an agility that belies everything you see and expect.

However, Lexus would be prudent to re-evaluate its suspension settings for our environment. The lack of compliance on coarse chip especially is something that might well cost sales. It’s a downside to having gone to fixed dampers rather than the adjustable multi-mode types favoured by the rival brands. Fact is, the GS-F can feel incredibly busy and harsh, in a manner unbefitting an executive sedan. A smoother ride, at least when driving in the softer dynamic settings, would do it the world of good.

Verdict

Much of what defines the GS-F is reflected by the maker’s determination, yet again, to fight in a specific sector with its own tools and on its own terms.

The quality of the engineer inputted into this car is undeniable and is a factor that provides it with ability to do well in driving circumstances that perhaps it was not wholly cut out for.

The GS-F appeals on price and as an executive express but nonetheless feels half a step behind those cars that it seemingly wants to emulate, at least to some degree.