BMW 3 Series v Audi A4 v Infinit Q50 v Lexus IS v Mercedes C-Class comparison review

Pay attention Australia: this could be the first of the ‘new’ traditional rear-wheel drive sedan stoushes for our post-Falcadore future.

First published in the December 2014 issue of Wheels magazine, Australia’s most experienced and most trusted car magazine since 1953.

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WHEN the Falcon has flown and the Commodore has sailed into the sunset, will comparing the latest C-Class and 3 Series become the Holy Grail? Will Mercedes v BMW become the default shootout in the pages of Wheels, the results anticipated beforehand and debated in forensic detail afterwards?

These Benz and BMW sports sedans are already fierce rivals and their sharp, rear-wheel-drive involvement and three-box shapes connect with our automotive hearts and heritage. We understand and appreciate this stuff; it moves us in more ways than one.

Our interest in them is more than merely theoretical. On 2014 sales figures, the C-Class and 3 Series are the third- and fourth-most popular medium sedans bought in Australia, trampling over everything bar the fleet-fodder Toyota Camry and commendable Mazda 6.

Our appetite is also increasing for them and their ilk as part of a general hunger for all things prestige and luxury. That’s why there’s no shortage of direct rivals lusting after a share of the action in a segment where affordability is yet to become a distant memory and aspiration is at its height.

Which is why we’ve lined up Merc’s new W205 C250 and BMW’s two-year-old F30 328i with another long-established foe, the Audi A4 2.0 TFSI quattro. Facing off against the Germans are two recent Japanese arrivals, the Lexus IS300h F-Sport and Infiniti Q50 3.5 Hybrid S.

Five for the money

The arrival of the new C-Class is what led to this examination, and we’ve stepped up from entry-level to a place where there’s a little more creature comfort, performance and, of course, a bigger price tag.

Audi aside, these cars – without options and before on-road costs – sit in a narrow band from $67,900 (Infiniti) to $69,400 (BMW). Our Ambition-spec A4 is $59,900, but it’s mechanically identical to the $67,800 S Line, which was unavailable for this test.

Superficially, these cars are similar. They’re all around 4.7-4.8m long, and all offer the expected equipment – a full suite of airbags, active and passive driver aids, sat-nav, leather trim, modern media and communication tools.

But look a little harder and you’ll find the key differences that distinguish their characters.

The Audi is the only all-wheel drive; the Infiniti is the only V6, and a big, brawny one it is, too. The Lexus is the only naturally aspirated four-cylinder and the only one with standard (note that word) adaptive suspension. The two Japanese cars are petrol-electric hybrids; the three German cars are turbo-petrol 2.0-litre fours. The IS uses a continuously variable transmission, the A4 and Q50 both drive through dual-clutch gearboxes, while the Benz and BMW rely on traditional torque-converter automatics with seven and eight speeds respectively.

There’s even a global production first – steer-by-wire in the Q50.

All offer some form of driver tuneability for various aspects of the mechanical package. This varies from almost none in the Audi to the comprehensive individualisation offered via Benz’s Agility Select dial (see breakout).

THE B8-series A4’s time is nearly up, yet yesterday’s car is generally pleasant, functionally earnest and very familiar. However, the front seats are flat, the vinyl backing is cheap, it has the noisiest cabin, and the lack of toeroom doesn’t help rear-seat passengers. Reflecting its age, this was the only car that came with a spare tyre, albeit a space-saver.

Benz has cascaded – rather than trickled – into the C250 a package of class-leading safety features that we were marvelling at in the S-Class limousine and E-Class mid-sizer barely two years ago. Among other things, it can autonomously brake for traffic and pedestrians, follow vehicles at speeds up to 60km/h and stay between lane markings. All this for a modest $1000 price rise makes the C250 good value, even before a new architecture and engine are taken into account.

Not content, Benz has completely overhauled the C-Class cabin, and the drooping interior now walks a fine line between gauche and elegant.

The aged Audi sits at the other end of the scale, conventional and forgettable, while BMW has been only a little more daring. The Lexus has good bits borrowed from the LFA – including a moving instrument meter – and bad bits that confuse. The Infiniti is by turns luxurious, complex and distracting.

All five fit four adults efficiently, but struggle to accommodate that third rear-seat passenger. It’s the price you pay for driven rear wheels; the diff and transmission tunnel demand space. But the payback is performance delivery and dynamics that can raise cars above mere transport.

Bliss, in its element

This is where the BMW makes its mark. The safe exterior styling and acres of interior plastic are forgotten once you snuggle in and go. No other car here has its sheer ‘Sunday morning drive for the hell of it’ appeal. The new-generation engine responds exultantly and disposes of everything here in a straight line – other than the he-man Infiniti – with a snarl.

There are tremendous reserves of grip, poise and adjustability, all of it aided by the F30’s low weight; the benchmark here at a claimed 1455kg.

There’s a big ‘but’ looming, though. Our test car had the optional M adaptive suspension, which lifts ride and handling significantly above the standard passive set-up. The take-up rate among buyers has been low, but if you relish driving, tick that box. You shouldn’t have to; BMW should make M adaptive standard for this car, as it has for the 428i.

Punting the BMW along a challenging road is a real joy once you figure out the Driving Experience Control. It offers Eco Pro (freeway cruising only, please), Comfort (dampers too floaty, yet that’s the default), Sport (the best choice in our view) and Sport+, which raises the threshold of traction control intervention. Opt for Sport, flip through the lovely ZF eight-speed ’box manually and you wouldn’t want to be in any other car in this group.

Feedback flows into your fingers through the electric-assist steering, and through the front and rear ends into your posterior, which remains unpuckered despite higher cornering speeds than anything else in this group.

To pucker, push here

Push along in the Infiniti and puckering comes as standard. At best, the Q50 is benign; at worst, it’s downright dangerous. That’s in Sport mode, which makes the steering too heavy and too quick, so you are constantly turning in too deep on corner entry, then correcting. While you’re at it, the front-end grip is only passable and the rear is dancing around on corrugations, the brakes refuse to act progressively and the Active Trace Control – which brakes individual wheels – aggressively clamps and unclamps, unsettling the car. Apparently Sebastien Vettel tuned this car. Maybe Dan Ricciardo should do the next one.

Driver after driver emerged from the car shocked at how little confidence it inspired. The Q50 wants to be a sports sedan – it looks keen with its raked-back headlights and low nose, but this promise is a deceit. A Commodore SV6 or Falcon XR6 would drive rings around it.

Dialling back the aggression is the only way to manage the Q50. Set the steering gearing to Casual, effort to Light, Trace Control off and Active Lane Control minimised. Even then the Q50’s cruising ability is marred by the worst ride here, especially at low speeds. Rolling on low-profile 19-inch run-flat rubber can’t help, but the Benz rides on the same set-up and is a far better effort.

The Q50’s beaut big engine is the car’s greatest asset; enough strength to brush off a near-1800kg kerb weight, yet still capable of delivering competitive fuel economy with the aid of its hybrid system.

Getting on, but still good

The lack of digital chassis adjustment is no impediment to the Audi. Tap the brake for a bit of weight over the nose entering the corner to keep understeer at bay, then rely on the self-locking centre diff to push and pull you up the next straight. Meanwhile, that excellent engine and snappy gearbox do their zestful thing.

Yes, the steering goes through a mushy stage as you turn off centre, and if you’re really pushing hard the handling gets loose and sloppy. But this is that rare Audi that has aged well. Apart from excessive cabin noise, the A4 is still fundamentally competitive, and more fun than its plain exterior suggests.

City winner, country grinner

The Lexus could use the A4’s drivetrain. The IS hybrid is by far the most economical. It’s the quietest and its ride at low speeds is a class above the rest. Its EV-aided tip-in acceleration is also outstanding. Around town, this car is a winner.

The F-Sport remains interesting beyond the ’burbs, when the pace builds and corners loom. Its nicely shaped sporty exterior indicates how it drives, with a playfulness to the steering and chassis that puts a grin on your face.

Unfortunately, that’s supplanted by a grimace as the others dash off up the next straight. The naturally aspirated 2.5-litre four is simply outclassed, farting out a sad exhaust note as it fruitlessly chases along. It’s nothing a 2.0-litre turbo wouldn’t fix, and soon will.

Fresh take on what’s possible

The new Benz demonstrates what’s possible, upgrading from the W204’s 1.8-litre turbo-petrol four to a quieter and more powerful, torquey and economical 2.0-litre. Allied with the lighter and stronger MRA platform, the C-Class continues to be an outstanding all-round drive.

Our test C250 came fitted with optional AMG sports suspension and Airmatic air springs, the latter being a first for the category. But, while there’s no doubt they round off sharp bumps and allow a choice between floatier Comfort and tauter Sport settings, their inclusion is not a deal-breaker in the way M adaptive is for the BMW.

That’s because the C250’s standard passive set-up has been well tuned to cope with all sorts of challenges, impressing us in the same way the W204 did back in 2007. Yes, Airmatic definitely adds control and comfort and is worth the investment. But the lowered AMG tune on our test car seemed superfluous, really.

The C250 can’t communicate and involve like the BMW does on adaptive dampers. The engine doesn’t have the same verve, either. That margin comes into sharp focus on one challenging climb and descent section on our test loop, where a series of corrugated closing-radius off-camber turns flow into one another, a drop-off one side and a rock wall the other. The BMW settles onto its outside rear wheel and devours this stuff, delivering more confidence and demanding more commitment turning in, while driving hard and clean on the exit. There’s movement through the rear end and steering wheel, but it’s feedback, not oafishness.

The Benz chases gamely, but body movement is more noticeable, less controlled. The car teeters a little, creating a small question mark in your mind. The steering is lighter and less defined, the engine response strong, but just a touch hollow through the mid-range compared with the BMW’s urge.

But remember, the BMW crests the climb with the Benz chasing hard; the rest are still coming behind. In the case of the Infiniti, far behind.

Refinement seals the deal

The C-Class more than redresses the balance when the pace is toned down and the driving reverts to everyday stuff. Then, the quietness and calm of the cabin is exceptional. At highway cruising speeds, the engine can barely be heard; the wind rustling off the exterior mirrors is more obvious. The C250’s ride is also a step ahead of the BMW, both clearly benefitting from how far run-flat tyres have come. It’s this refinement that helps seal the deal for the C-Class.

The Infiniti is a good concept tragically underdone, the A4 a good car that’s aged and the Lexus a good chassis in need of a great engine. The only car that really threatens the C250, appropriately enough, is the BMW. It’s a wonderful drive that deserves standard adaptive dampers and a cabin that feels and looks more special.

The Benz is not only the newest but also the most complete. That’s what makes it the most convincing. It has leapfrogged the BMW, as we’re used to seeing Falcons and Commodores do to each other in Wheels shootouts. The C250 claims the ascendancy, but only establishes enough gap to motivate, not deter, the lads in Munich.

What adds spice is the prospect of the other brands proving they can do the job. Maybe Audi with the next A4, Lexus with an upgraded IS drivetrain, or a new Infiniti chassis. Volvo could spring a surprise with its new platform and engines.

This is a dimension the Falcon v Commodore fight rarely had. It’s why 3 v C v the rest is something special, and why we’re already looking forward to the next one. You should be, too.

Power play

DRIVING the C250 sharpens our anticipation for the hot Mercedes-AMG C63. There is real dynamic ability in the new MRA architecture for the team at Sindelfingen to tap. They’ll need to if the car is to cope with its new 375kW/700Nm 4.0-litre twin-turbo V8, a wet sump version of the GT AMG donk.That’s 25kW and 50Nm up on its glorious 6.2-litre naturally aspirated predecessor, and well ahead of the brilliant new M3/M4’s 317kW/555Nm twin-turbo six. The sedan and wagon, unveiled at the Paris show, go on sale in Australia around March. A coupe and maybe a convertible will follow in 2016.

Join the pack

JUST as they target the mainstream C and 3, so the challengers are after a share of the high-performance market. Infiniti is weighing up whether to build its Q50 Eau Rouge, powered by a 418kW version of the Nissan GT-R’s twin-turbo V6 engine. Next year’s B9 Audi A4 will spawn an RS4 tipped to trade the atmo V8 for a return to a twin-turbo V6. A second-generation Lexus IS F using the naturally aspirated 5.0-litre V8 from the RC F is being considered. And then there’s the Jaguar XE SVR, developed by its Special Vehicle Operations. A huffed 5.0-litre V8 is likely.

Wiretapped

THE Infiniti Q50’s steer-by-wire Direct Adaptive Steering works by electronically transferring the driver’s input to the front wheels, where a high-response actuator drives the steering rack. Steering is adjusted via a touchscreen, with up to four pre-set modes and a personal setting that allows the driver to mix and match effort and response. The system comes with a triple-mode back-up (three separate electronic control units), 400,000km of real-world testing and the fail-safe fallback of a mechanical steering linkage.

Make a move

REMEMBER when dialling up the fun was just a matter of switching off the stability control? The new Benz’s Agility Select system adjusts the drivetrain through Eco, Comfort, Sport and Sport+ modes, while the steering has Comfort and Sport modes. Infiniti’s Drive Mode, BMW’s Driving Experience Controller and the Lexus Drive Mode Selector all do similar things, although the F Sport adds adaptive dampers.

The old-school A4 gearbox just has Drive, Sport and Manual modes.

Verdict