M4 v RC F 17b

Lexus RC F v BMW M4 : Comparison review

It is quite literally a fork in the road moment. Just after the long, sweeping hairpin on Jenolan Caves Road, on the western side of the Blue Mountains in New South Wales, the BMW M4 and Lexus RC F are parked on a little side road.

The duo of two-door coupes are tinking away, heat pouring from their wheelarches after up-and-back runs of the main road and then the side road.

The first road has perfectly smooth surfacing, a mixture of tight corners and flowing S-bends with ideal sight lines; the other plunges into a valley, with coarse chip and broken surfacing until you clamber over a rickety wooden bridge and tackle an even tighter, bumpier hill climb.

The roads are as disparate as the cultures of Germany and Japan, and as much a contrast as the 3.0-litre twin-turbo six-cylinder and 5.0-litre naturally aspirated V8 engines under the bonnet of the M4 and RC F, respectively.

More importanty in terms of this test, each of these coupes has won our hearts on only one of these roads – and at this point not even a fork prodding us in the back could force us to choose one convincingly over the other.

You may have read that the BMW M4 coupe and its new M3 sedan sibling have been met with mixed response since their unveiling last year.

From where this tester is sitting the new F80-generation of the M Division’s finest has become so much more faster and luxurious, but also both boosty, whooshy and remote, where the previous E92-generation was slower, but immerseful in its sound and response.

But that is not the end of the story, because perhaps those chief criticisms were thrown into the spotlight by testing the new M4 against a master of communication, thunder and awe, the very old-school Mercedes-AMG C63 AMG last year (read the full comparison here).

Every time I drive the new M4 I’m willing to give it another shot; I want to love it, hopelessly and desperately.

New competition arrives today in the form of the Lexus RC F.

Don’t know about you, but I’d always pegged the previous-generation Lexus IS F as more of an Audi S4 competitor than one for the RS4, M3 and C63. Over its lifetime the IS F became such a likeable car – from being a little bit average at launch in 2008, it had so many updates over its life cycle that it progressively became really rather good. But it was always a bit sub-M3, and that was reflected in circa-$125K pricing.

This new RC F boasts two doors instead of four, and the brand insists it isn’t just a progression of the outgoing IS F. Instead the RC F has been benchmarked on the Lexus CCS-R racecar, essentially a stripped-out, hardened IS sedan that I’ve actually had the privilege of driving at Fuji speedway last year.

Specifications reveal the RC F is much, much less stripped out. Tipping the scales at 1780kg, the new Lexus is an absolute porker for a compact coupe. Although though we’re testing the entry car priced from $133,500 plus on-road costs, that kerb weight figure is for the more expensive variant called the RC F Carbon, priced from $147,500.

The extra $14,000 over the standard RC F sees the addition of a carbon-fibre active rear wing, bonnet, roof panel and interior trim saves 9.5kg, for example. But even the standard RC F gets more equipment than the M4, despite the BMW starting from a much higher base of $166,430 plus on-road costs.

Optional are adaptive LED head-lights ($2360, but with auto high-beam that blocks out forward or oncoming cars not available on RC F), and lane departure and collision warnings (packaged for $900 with light auto braking not available in the Lexus).

Surprisingly, the active cruise control standard in the RC F isn’t at all available in the German.

In the M4 you can get a no-cost option electric sunroof to match the model from Japan, but you’ll need to forgo the standard carbon roof (and when you get the latter in the Lexus you lose the hole in the roof anyway).

In either case you get premium audio systems – 16-speaker, 600-watt Harman Kardon in BMW; 17-speaker, 835-watt Mark Levinson in Lexus – with digital radio tuners, and premium leather-trimmed and electrically adjustable sports seats.

But let’s just say the BMW iDrive system works with far greater ease of use and intuition than the Lexus Remote Touch equivalent that requires your finger to guide over a touch sensitive pad on the console; particularly with a firmer riding coupe it is unmanageable.

It also gives you haptic feedback, a bit like a 1980s arcade-game joystick; and it feels just as horrible.

With a bright 8.8-inch colour display and a more in-depth variety of (optional, but for only $250 per three years) internet connectivity functions, the M4 also looks so much more premium than the smaller RC F display.

Indeed if it’s a feeling of expense you’re after, the lashing of leather across the dashboard of the BMW has it all over the plasticky Lexus that is barely differentiated from the RC 350 that costs around half the price; save for some Alcantara over the main dials.

Disappointingly, in the M4 a colour head-up display is a hefty $1700 extra, the especially cool option of which casts an M tacho on the windscreen when you’re in its sportiest of modes and has a shift point indicator that lights up yellow then red as you're approaching redline – a bit of colour and sports for the driver in an otherwise low-key luxury interior. We like it a lot.

Above: BMW M4 (top); Lexus RC F (bottom).

The Lexus has its own cool gadgets that embrace Japanese culture as much as the manga, origami-inspired exterior that to some eyes looks contrived, but to ours just looks great because it embraces its own backyard and doesn’t try hard to be Euro.

Relating to the standard “torque-transfer type torque-vectoring system”, drivers can select between Standard, Slalom and Track settings – and inside the LCD speedometer you get pictures of the city, mountain pass and race circuit respectively when each is selected.

How very cool and Japanese.

Consisting of two motor control units, two multi-plate clutches and planetary gears for the driveshaft, the torque vectoring system along with altering the stability control calibration, prioritises agility for slalom work and stable behaviour for track work. Presumably, it also tries to manage the shifting of the RC F’s considerable weight when pressing on.

BMW, of course, has its famed Active M Differential which aims to do much of the same thing without the pidgeon-holing and graphics. Advanced electronics and an electric motor can ‘lock up’ the mechanical limited-slip differential even before slip is detected to enhance traction and stability.

To level out the task of finding out which system works best, both test cars arrive wearing the same 275mm-wide, 35-aspect Michelin Pilot Super Sport 3 tyres on the rear wheels (both also get 255mm-wide tyres at the front).

Fixed suspension is all that’s available in the RC F, though, where the M4 gets more sophisticated multi-adjustable damping that should help with ride quality in its softest Comfort mode, while tightening body control in the harder Sport and Sport+.

That isn’t the only area where the Lexus starts to feel a bit old school.

It retains the same 5.0-litre naturally aspirated V8 engine from the outgoing IS F, though it has been heavily upgraded with forged connecting rods and titanium valves allowing it to rev to 7300rpm.

It needs almost all of those revs (7100rpm) to produce its peak 351kW of power, while 530Nm of torque is only on tap between 4800rpm and 5600rpm.

Even its eight-speed torque converter automatic seems to be a bit yestertech alongside the seven-speed automatic dual-clutch transmission in the M4.

Much has been written about BMW downsizing its most compact M car’s engine to a 3.0-litre six-cylinder unit equipped with two turbochargers. There is no denying the results – 550Nm between 1850rpm and 5500rpm, and at that latter point 317kW comes into play and holds strong until 7300rpm.

BMW also doesn’t require you option equipment for it to shed kilos, with lots of aluminium and carbonfibre bits as standard helping it weigh a lithe 1537kg – an astonishing 243kg less than its rival.

Standstill to 100km/h comes up in just 4.1 seconds, compared with 4.5 seconds for the Lexus.

On the smooth bitumen approaching our fork in the road, the gap feels much wider than those acceleration figures suggest. The M4 feels unbelievably fast, particularly through the mid-range.

The engine sounds loud but also coarse and synthesised, and nothing like a six-cylinder, although if you’re really on the throttle and slamming up through the gears it can win you over with its sheer torrent of growl.

Unless you’re talented enough to slide the BMW in anti-social power oversteer through corners – and most of the testers who love this car thinks this is what you should do on a legal road – the M4 becomes a point-and-shoot M car rather than one in which to indulge.

Turn the stability control systems off (disappointingly, you have to at least go to M Dynamic Mode as it constantly fights you) and the way the M4 steps up to meet your commitment level is astonishing. The rear slips, but it dances rather than swings or attempts to spin you into the scenery, while the front is quite delicate.

There are a few peculiar traits, however.

You can really push the front end hard into a corner, but the more you do, the more patient you have to be to get on the throttle or the M4 will snap at a feather press. Conversely, if you judge a mid-to-high corner entry speed the whole car will feel beautifully balanced, but again, you’ll only need millimetres of throttle to get the rear-end playing. Get it right, and it will be the most lovely, tiny dancer.

For those – like me – who loved eeking out rear attitude via finely metered throttle movements while an engine wailed and delivered meticulous amounts of more grunt to the wheels, the touch-and-boost style of the new M4 disappoints.

That’s especially the case when the steering threads no real feedback to the driver’s hands, which makes judging grip levels a guessing game.

The question also has to be asked why the engine needs to rev to 7700rpm when it gives all its attitude in the first bit of throttle and throws so much torque to the rear wheels at 1850rpm. It feels in some ways like the M4 was built to a criteria.

The Lexus cannot hope to catch the BMW through this smooth, twisty road.

It pushes its nose wide earlier, requiring a lower corner speed than its rival. Yet it’s also harder to keep its engine singing, and when the RC F does lunge from those corners from a lesser speed, it pants to keep up.

Then we turn off and let the brakes cool, before tackling the hillclimb.

The Lexus may only have fixed suspension, but it does a brilliant job of absorbing impacts and controlling its body. It simply streamrolls bumps, allowing its driver to press on and on whatever the road surface.

The auto is reasonably quick in manual mode, accessed via the steering wheel-mounted paddleshifters, and on the hillclimb hearing that joyous V8 soaring at the top end of the tachometer just feels right and natural.

The RC F loves quick changes of direction so long as the corner entry speed isn’t too high. Luckily you get lovely feedback through the steering wheel, and that naturally aspirated engine means that, yes, hallelujah, you can adjust its line on the throttle as soon as you know the front end is loaded up.

Right here, the Lexus shrinks around you to feel like the lithe little coupe its engineers wanted it to be.

Says chief engineer Yukihiko Yaguchi: “my development concept was blast through S-bends under any conditions”. We hear you, mate.

Driving the M4 at the hillclimb reminded me of being a child, hanging onto the front bar of a wooden roller coaster, all white knuckles, back bracing the impacts but loving the ride.

Trying to feel grip levels at the front and judge throttle input mid corner is difficult, so you end up using up all its turbo boost on the short straights, and brakes at the end of it going into a really tight bend less quickly.

Despite having three suspension settings to choose from, none feel at home on a country road. Comfort allows too much float, yet both sport modes crash and thump through the surface, even visibly shaking the dashboard at one point. In any case, composure is lacking compared with the drum-tight Lexus, so you end up getting little hops and skips sideways that destroys your confidence.

Although both cars wear the same-sized tyres, the lighter BMW actually feels more heavy footed, as though you’re trying to walk down a road in ski boots.

So do you take the coupe that hits higher highs, that amazes you with straight line speed and the sort of light and balanced smooth cornering that would keep a two-seat Porsche Cayman on its toes? Or do you take the coupe with a greater breadth of all-roads talent, the one that communicates more clearly and sings more naturally?

That is our discussion point at this fork in the road, and still there is no answer.

Of course, though, these contenders must prove themselves beyond these two roads, so we ponder that thought while heading two hours back to the big smoke.

On the long, slow slog over the Blue Mountains, it’s the Lexus that feels less responsive than you’d expect for the price, and its transmission in auto is quite doughy and slow witted. That said, the BMW also can feel a bit laggy right down low in the rev range, and its dual-clutcher can surge and stumble on light throttle.

When the hills flatten out to the freeway, the M4 suffers noticeably more road roar that can be downright deafening at times.

A the service station, both claimed combined cycle fuel consumption figures blew out, unsurprisingly. But highlighting that even frugal new turbo tech will drink aplenty in hard conditions, the M4 that claims to drink 8.3 litres per 100 kilometres blew out to 15.8L/100km on test; the RC F starts from a higher 10.9L/100km but narrowed the gap in identical conditions to 16.7L/100km.

Still, that a much faster car slurps less fuel is a win-win situation.

Back around town, and the fixed suspension on the Lexus proves quite abrupt and generally unsettled. The BMW can still be a bit clumsy, but it irons out more imperfections and is generally smoother than its rival, especially in the softest comfort mode (the pick of the three).

Along with a more premium interior with a far more sophisticated infotainment system, it is hard to not call this contest in favour of the BMW M4.

The problem for the Lexus RC F is that while it feels quite fun and communicative, it also doesn’t feel like a car that costs $133K.

At times the M4 feels more premium that its extra $35K indicates. Compounding the problem is that the excellent RC 350 F Sport at $75K has a lot of the F car’s agility and unless you’re right up it doesn’t feel much slower.

Seriously fast, yet able to seat four in luxury, the M Division’s smallest model has never attempted such a broad range of attributes. With extra communication and composure it could be the perfect sports coupe, but for now it’s just going to have to settle for fending off a Japanese rival. Meanwhile a certain brand new German competitor starting with ‘C’ is lurking just around the corner…

Click the Photos tab for more images by Christian Barbeitos.

- shares