BMW M4 convertible auto – is more muscle more magic?

With the introduction of the new M turbo engine, the BMW M4 rounds off the all-turbo BMW M line-up.

All BMW M cars now turbocharged

As turbocharging came back into fashion in the BMW 335i coupé in 2006, who knew that the turbo would take over across all BMW vehicles… including, one day, the M cars?

It has happened – with the M5, X5 M, M6 and X6 M all using a V8 turbo, the time has come for M3 and M4 to get up to speed (and lots of it) by using turbo too.  The 1st 2 generations of M3 we had in South Africa were exciting metallic-sounding high-revving BMW M Power straight-sixes.  The previous M3 had a distinctive shrieking V8 – all natural air inhaling.

Now the time has come for a return to the straight-6 BMW is so famed for, but this time with turbo air boosting.  On paper the power difference between the previous M3 4.0 V8’s 309kW at 8300 r/min versus the new turbo 3.0 6’s 317kW (from 5500 to 7300) may not seem much, but the turbo brings along a change from 400Nm in the V8 to a more-than-enough 550Nm torque in the new M 6-cylinder cars.

From start-up you hear this is no ordinary engine.  The mix of bass with a raspy exhaust gives a sound unlike any other BMW before it.  Sure, a 3.0-litre straight-6 turbo has been winning Engine of the Year awards for BMW for years, and is familiar across all BMW Series and X and Z cars.  But in the M3/M4 it sounds completely different – more hard-edged, and way waaaaay louder.

Purity or computer – which is a key ingredient in an M car?

With BMW’s focus on building Sheer Driving Pleasure, the BMW M cars used to spell the epitome of this now disused brand slogan.  Whether the shrieking six in the M3 or Z4 M, or the gravel-howling V10 in the M5 and M6 – the drive was with the aim to provide sheer driving pleasure.  They had a driving purity.  Smart engineering to create exciting engines.  M was not for Motorsport but for Magic.

In the new turbo V8 M cars, the M engines are so boosted and forced to produce the biggest numbers, they lose focus on actually sounding good or having any real character (apart from being powerful) and thereby lost focus on driving joy.  Is the new 6-cyl turbo M car any better?  In the BMW M4, power and torque is served up instantly, at any spot on the rev counter.  The sounds are loud, and fluctuate between a bass with an exhaust buzz on lower revs, rising through a metallic rasp (trying to replicate the E46 M3 sound, but not always able to recreate it) rising to more straight-6 noise… but not typical BMW straight-6 or BMW M sounds, nor an exciting-to-drive linear power delivery. 

No need to rev it – the turbo will do the work for you across the rev range.  The exhaust is very loud, and can be heard from a distance, with a loud cold start-up (as a neighbour with an M4 coupé in his garage likes to wake up to in the mornings).  Thankfully the M4 sounds like a 6-cylinder, where the V8 M turbo cars sound like 4-cylinders, which is just wrong!

Previous M3 cars had a certain quality about them – a purity.  A sense that a lot of engineers spent late nights getting the engines tuned to perfection.  On the new M3 and M4 cars, it seems someone plugged in a laptop to remap the engine power delivery and slide the turbo control unit to its maximum boost setting.

Fast and loud, but where is the purity?

Fake engine sound?

The BMW M4 is fitted with a sound synthesiser, but not the type DJ’s use.  The speakers in the car play a soundtrack of the engine.  So what you actually hear inside the car is a recording of an engine sound, rather than an authentic engine sound.  Sorry, but that is just fake.  Do people want to hear this rather than a pure BMW M engine sound?

The super-loud exhaust can also perform an orchestra of pfff-blaahhrrppp, much to the joy of teenage boys, and much to the annoyance of elderly ladies in shopping mall basement parkings.

Muscle power – athlete or body-builder?

The BMW M4 convertible auto as tested has so much torque muscle, it is hard to put down.  Try accelerating hard off the line, and all you get is lots of wheel-slip as the rear tyres, despite being being 275 wide on the optional 19-inch wheels, cannot get all that torque down on the road.  You could use the Launch Control, but this is a procedure to follow, which is not what you want to do each time you want to set off quickly, and is very harsh on the drivetrain.

Drive in town and floor it to quickly overtake, and the traction control light goes crazy as it tries to hem in the wild horse.  Hoooah, too much… this driver better lift off.  The M4 convertible is heavier than the M4 coupé, due to the extra roof mechanisms and extra bracing to keep it stiff.  With the roof folded into the boot, which hoped would add extra weight onto the rear for extra tyre grip, it made almost no difference.

The Active M Differential is standard on all new BMW M3 and M4, and this works well in getting traction when G-forcing through fast bends.

Achieving a good balance between power and muscle definition is what athletes strive for – the same balance is an art which very few cars catch.  Body-builders may look imposing with over-size muscles… but do they really look good, or is it just one big show-off?

Too much mega-mass and artificial hormones have seen the muscles grow so much that they cannot sprint like athletes can.  Where previous M cars like M3 and Z4 M were athletes, the new M3 and M4 are body-builders.  Lots of muscle… but too much, so just unable to use it.

Make an effort to get those special M moments

The difference between an appliance car and a driver’s car is that, in a driver’s car, you hunt for some special moments.  Where one is just a means of transport, the other is created to give the driver the occasional thrill.

The M4 is very busy and buzzy – the engine just wants to be wild and free, and the exhausts are exhausting… the car feels so busy with surges of tailsliding and lunges forward, with a constant push-pull of buzzy exhaust and fake engine sound.

So which is the BMW M4 convertible?  With all its computer-turbo torque and fake engine sound, are sweet moments in the package?  Fortunately yes!  Use the accelerator in the right way (don't be too harsh on it) and allow the BMW M4 to let its turbo 6 and brilliant M-DCT dual-clutch automated manual do the work, and you can hit that sweet spot.

Do not let the Austin Yellow goldish paintwork overwhelm the driving experience, which this loud colour can do – imagine it in Yas Marina Blue (that baby-blue) or white or black, and the car’s strengths comes through.  The goldish-yellow was as attractive as pollen to a bee, which came to try to pollenate the bonnet of the M4… a bee on your bonnet rather than under it. 

The yellow and blue also go back to the E46 M3 cars, which were available in distinctive Dakar Yellow and Avus Blue, as do the metallic raspy exhaust (but much less so).

Nice toys and jewellery

The M4 convertible has a selection of fine jewellery to make it stand out – the broad stance and angry front and rear bumpers, silver slivers braced across the front side air intakes, proudly wearing M4 badges.  4 typically BMW M exhausts sprout and shout out the rear.

The M seats have illuminated M badges, lighting up in soft white – a nice piece of jewellery.  Look closely at those 19-inch wheels and you’ll notice these are not all-black, but cleverly finished in diamond-cut burnished for a high-sheen duo-tone look.  These cost R 25 500 for the set, but you really do not want the standard plain-Jane 18-inch wheels.

Have you noticed the new M3 and M4 cars have “hidden” side indicators in the mirrors?  When off, you see just the blacked-out housing, but when activating indicators, a small strip of orange backlit lights come to life.

Toys include the Air Collar, fitted as standard to BMW M4 convertible, which blows hot air from the front seats headrests.  Seat heating is standard for the front, but strangely the rear seats are only optionally heated in the 4-door M3, rather than in the M4, which especially in speedy open-roof drives leave the rear seat people in cold air.

Go for the Full leather Merino which covers the dashboard and door top rolls, with some tasty stitchwork – with this, the M4 cabin feels really special and rich.

Comfort Access keyless un/locking is included for the M4 convertible.  Xenon headlights are standard, but LED headlights light the way at R 23 500. 

Configure your preference of modes for power (driving modes Comfort, Sport and Sport+), suspension, steering, gear shifts and head-up display through the iDrive menu to set up your M Drive 1 and M Drive 2 (called up instantly through the steering wheel switches).  Interestingly, there are also buttons on the centre console next to the gear selector with which you can select Comfort, Sport and Sport+ modes for each of the driving mode, suspension and steering settings, so you could have a combo of Sport+ driving mode with Comfort suspension with Sport steering.

Things like Navigation, electric seat adjustment, ConnectedDrive Services (BMW Online, BMW Apps) and Intelligent Emergence Calling (SOS) are standard. 

The Concierge Services option of R 3 200 is useful – choose this on the menu, and the car phones an operator (a real live human you can talk to) who can quickly provide information, or guide you to a hotel, and even send the location and route to your in-car navigation.  Amazing.

Competitors and pricing?

The M4 convertible is a 2+2-seater, with early-teen rear occupants not complaining about space.  The BMW M4 convertible competes against cars like the Audi RS5 cabriolet and Porsche 911 Carrera S cabriolet, which also have 2+2 seating.  The Mercedes-AMG C63 coupé is on its way, which will take the fight to BMW M4 coupé.

Pricing of BMW M4 start at R 1059 500 for the M4 coupé manual, and add +-R140k for the folding hardtop roof and the extra joy of roof-open driving, and you really would want the M-DCT gearbox (though steep at R 48 500 extra) to arrive at R 1 252 000, before options.  A BMW High Performance Driving Experience course is included.

BMW M4 convertible auto – is more muscle more magic?

The BMW M4 convertible has much more muscle and much more noise and toys than the M3 convertible it replaces.  Whether BMW M is merely keeping up with the times by adding turbo and lots of computers (and fake engine sound) or should M cars go back to offering pure driving thrills, is for you to decide.  More muscle does not always mean more magic.

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