BMW has been rolling out some intense products this year, especially the new 3- and 4-Series lineups, complete in their sedan and coupe variations. Beyond that, the M version of each have stirred even more commotion in the industry, but one car was missing – The M4 Convertible. Today BMW corrects that as the German automaker divulges all the details and images of the new 2015 M4 drop top.
If you’ve read anything on the new M4 Coupe, the convertible will be highly familiar. Power still comes from the 3.0-liter, twin-turbocharged inline-six that’s mated to either a six-speed manual or seven-speed M-DCT transmission. The other go-fast bits like the uncompromising suspension, massive brakes, and free-flowing exhaust are all carried over.
The big news with the car is its three-piece retractable hardtop. With the push of a button, the top folds itself like a piece of origami in just 20 seconds and at speeds up to 11 miles per hour. Cargo room has improved of the last generation M3 Convertible, gaining an extra 0.7 cubic feet of room with the top up and an impressive 7.8 cubic feet of extra room when the top is folded down. Unfortunately, the extra space and all the drop-top hardware comes at a heavy cost — an extra 525 pound cost over a comparable M4 Coupe.
The news of the M4 Convertible comes before its official debut at the 2014 New York Auto Show happening April 16. Though BMW is only jumping the gun by a few weeks, the information gives us a chance to really dig into the M4 Convertible once we see it roll across the all-important New York stage.
More details will roll out soon, so stay tuned.
Update 4/4/14: BMW has released lots of new details and images of the M4 Convertible.
Click past the jump to see the spy shots up close and to read more about the M4 Convertible
Updated 03/17/2014: According to BimmerToday, the new M4 Convertible will finally be unveiled later in April at the 2014 New York Auto Show - set to open its gates on April 16.
Updated 09/06/2013: Based on the recently announced M4 Coupe Concept, we have prepared a rendering for the upcoming M4 Convertible version. Basically we removed the roof and changed the color, but even so, the new rendering could be helpful to imagine the next M4 Convertible.
April 3, 2014 - BMW M4 Convertible takes one last session before official unveiling
March 20, 2014 - BMW M4 Convertible testing at Nurburgring
February 10, 2014 - BMW M4 Convertible testing in cold Scandinavia
From the side, it is crystal clear that we are looking at the M4 Convertible, thanks to the aggressive front apron, side skirts and the hard top with joints in it. The biggest difference between this and the coupe model is that Bimmer obviously restyled the trunk lid to house the convertible top.
Around back, the fact that this is an M4 is reassured by the quad trumpets blaring exhaust noise and the cutout in the rear bumper for the diffuser.
Sure it’s the same as the coupe, but with then retractable hardtop is stowed, something about that accent line makes it stand out even more.
Like its Coupe cousin, the M4 Convertible is designed to be as aerodynamic as possible, with a nicely sculpted front end featuring plenty of wind tunnel testing behind every curve. The lower fascia gets the same aggressive styling as the coupe version, making it a menacing object in the rear-view mirror. Besides looking good, the lower air intakes help cool the two turbos and the front brakes while reducing lift along the front axle. Optional LED headlights flank the iconic kidney bean grille.
The bulging hood continues the cohesive design from the coupe with its domed center section and hard creases dispersing from the front BMW Roundel. Hiding under the front clip’s paint are aluminum panels for the fenders and hood, helping keep weight down.
Around to the sides, the same strong belt line runs rearward from the side gill to the rear taillights. Sure it’s the same as the coupe, but with then retractable hardtop is stowed, something about that accent line makes it stand out even more. The rear haunches and the car’s wide rear track also stands out more. The narrow back seats visible with the top stowed visually shrink the interior of the car while the wide rear end make the car seem even wider and more sporty than it already is.
2015 BMW M4 Convertible - Exterior Dimensions
|Track, Front / Rear||62.16 / 63.11 inches|
Notable are the M badges on the bottom of the steering wheel and chrome-plated dead petal.
Things are very familiar inside the M4 Convertible with seemingly every interior component shared between it and the coupe. The interior layout is simple and easy to comprehend with the gauges and controls easy to read. The two main gauges remain analog in the center instrument cluster. The iPad-like infotainment screen returns along with the iDrive rotating knob perched on the center console. The HVAC controls retain their familiar buttons mounted mid-dash.
M specific stitching and badges help distinguish the M4’s interior from standard 4-Series convertibles. Notable are the M badges on the bottom of the steering wheel and chrome-plated dead petal.
The engine is able to produce and hold its full torque output from a low 1,850 rpm through 5,500 rpm where the horsepower takes over.
Like the M4 Coupe and M3 Sedan, power comes from BMW’s 3.0-liter twin-turbocharged inline six-cylinder. The engine features what BMW calls Valvetronic and Double Vanos to manipulate the camshafts’ operation, long with direct fuel injection. A double exhaust pipe system runs the length of the car, helping keep backpressure in check and the turbocharged symphony singing loudly. All told, the 3.0-liter kicks out an impressive 425 horsepower and 406 pound-feet of torque.
The engine is able to produce and hold its full torque output from a low 1,850 rpm through 5,500 rpm where the horsepower takes over. From 5,500 rpm on up to 7,300 rpm, the Six kicks out its 425 horses in a constant stream of power.
BMW offers two transmissions with the car: the standard unit is the sweet-shifting six-speed manual. The optional tranny is BMW’s seven-speed M-DCT dual clutch. Lighting fast shifts and the ability to drive in automatic mode make it a smart choice for those looking to daily drive their M4 Convertible. With that transmission selected and all the sport modes engaged, the M4 Convertible hits 60 mph in 4.2 seconds while the six-speed manual does it in 4.4 seconds.
Helping get the power down is BMW’s Active M Differential. The limited slip unit is intertwined with the Dynamic Stability Control system which communicates information like throttle position, yaw rates, and wheel speeds to help distribute the torque most effectively. The system also includes M Dynamic mode, which when its button is pressed, allow for more wheel-spinning shenanigans and highly-enjoyable oversteer situations to occur. Fun on the track – not so much in the rain, so use accordingly.
2015 BMW M4 Convertible - Drivetrain Specifications
|Engine Type||3.0-Liter I-6 Turbocharged|
|Engine Technology||M TwinPower Turbo technology with two mono-scroll turbochargers, High Precision Direct Fuel Injection, fully variable valve timing (VALVETRONIC) and variable camshaft control (Double-VANOS)|
|Output (HP @ RPM)||425 @ 5500 - 7300|
|Torque (LB-FT @ RPM)||406 @ 1,850 - 5,500|
|Transmission||Six-speed manual gearbox (optional: Seven-speed Double Clutch Transmission)|
|Acceleration (0-60 MPH)||4.4 Sec (W/ Manual) / 4.2 Sec. (W/ M-DCT)|
|Top Speed||155 mph|
Since the M4 Convertible isn’t official released yet, there’s no word on pricing. Taking an educated guess based on the M4 Coupe’s starting price of $64,000, we’d say the M4 Convertible will start a shade under $70,000. As always, expect BMW to have a rather pricing options list available for personalizing your M4.
The 2014 Audi RS5 Cabriolet features a monster of a 4.2-liter V-8 powerplant that delivers 450 horsepower and 316 pound-feet of torque to all four wheels. This is enough to launch the drop top to 60 mph in just 4.9 seconds and up to a top speed of 174 mph.
Unfortunately for Audi, its naturally aspirated format leaves it lacking in the torque department, which leads to significantly slower sprint time when compared to the M4 Convertible.
Gallery Audi RS5 Cabriolet
The M4 Convertible is a natural evolution for the car with all its heritage leading up to this point. Its power, poise on the road, and track-star attitude, the M4 Convertible will surely be a great car for drop-top fun. However with its added weight, the convertible won’t likely be the track star its coupe cousin will inevitably be. But that’s ok. The convertible fills a separate void in the market — one that is more boulevard cruiser and mountain pass runner than lap-time king. In the M4 Convertible, it’s more about the experience and the visceral feel of wind and sound of four angry exhausts pipes expelling curses than anything else. We can’t wait to get behind the wheel.
- Looks amazing
- Hard top makes it more usable day to day
- Driving dynamics won’t likely change that much
- Gains some 500 pounds over the coupe
- Slower than the coupe
- No solid pricing numbers yet
Gallery BMW M4 Convertible
The all-new BMW M4 Convertible arrives in US showrooms late this summer to join the M4 Coupe and M3 Sedan. The 2015 BMW M4 Convertible is powered by the same BMW M TwinPower Turbo 3.0-liter inline-six as its siblings. That engine produces 425 horsepower and 406 lb-ft of torque and can be mated to either a 6-speed manual or 7-speed M-DCT transmission. The new BMW M4 Convertible makes its world debut at the 2014 New York International Auto Show.
The new inline-6 M engine: High-revving, turbocharged unit combines the best of both worlds.
Like the new BMW M3 Sedan and new BMW M4 Coupe, the new M4 Convertible sees a return to an inline-six engine, as used on the second and third generations of this iconic open sports car. The new turbocharged engine combines the best of both worlds – reaching a maximum 7,600 rpm, it is unusually high-revving for a turbocharged engine, resulting in linear power delivery over a wide engine speed range and a soulful engine note, while M TwinPower Turbo technology ensures that peak torque is on tap over a broad rpm range. A further hallmark of this engine is its outstanding efficiency.
The new engine sees a power upgrade over the previous V-8 to 425 hp, which is delivered between 5,500 and 7,300 rpm. Peak torque has been increased by roughly 40 percent to 406 lb-ft, and is maintained over a very wide rev band (1,850–5,500 rpm). The sprint from zero to 60 mph takes the new BMW M4 Convertible just 4.4 seconds with the 6-speed manual. Equipped with the 7-speed M Double Clutch Transmission, this number falls to
4.2 seconds. Top speed is 155 mph (electronically limited). The BMW M TwinPower Turbo engine hits maximum revs of 7,600 rpm, in keeping with the typically high-revving character of M engines.
The M TwinPower Turbo technology comprises two fast-responding mono-scroll turbochargers, High Precision Direct Injection, Valvetronic variable valve timing and Double-VANOS continuously variable camshaft timing. Valvetronic and Double-VANOS work in tandem to seamlessly control intake valve lift. The result is smooth and efficient power delivery, very sharp response and reduced fuel consumption and emissions.
The six-cylinder engine features a closed-deck crankcase design which is very rigid and allows cylinder pressures to be increased for improved power output. And instead of liners, the cylinder bores feature a twin-wire arc-sprayed coating, which results in a significant reduction in engine weight.
Engine weight is further reduced by the forged, torsionally rigid crankshaft which, as well as saving weight, also provides increased torque-carrying capacity. This significantly reduces rotating masses, resulting in improved throttle response and acceleration.
Innovative technologies delivering top-level performance.
Power transfer in the BMW M4 Convertible is via a standard six-speed manual gearbox. Available as an option is the seven-speed Double Clutch Transmission M-DCT, which allows the driver to change gears not only using the selector lever in the center console but also via the shift paddles on the steering wheel. This transmission effectively combines two gearboxes, each with its own clutch. This means gear changes are executed with no interruption in the flow of power – and the shift processes are therefore shorter. Drivelogic allows the driver to select from different shift modes, which see the M4 Convertible adopting a particularly comfort-oriented, economy-focused or ultra-sporty approach to gear changes when in automatic mode. The Launch Control function also integrated into M-DCT enables optimum acceleration off the line.
The standard Active M Differential optimizes traction at the rear axle. The electromechanical steering system, meanwhile, represents a new development from BMW M GmbH and is the critical component in the link between driver and car. It offers the gifts of direct steering feel and precise feedback. The integrated Servotronic function electronically adjusts the level of steering assistance according to the car’s speed, providing optimum steering characteristics at all speeds. Three steering settings (COMFORT, SPORT and SPORT+) can be selected at the touch of a button to adjust the level of steering assistance to the situation at hand and to the driver’s personal tastes.
The optional Adaptive M suspension likewise comes with COMFORT, SPORT and SPORT+ modes. The BMW M4 Convertible is equipped as standard with M compound brakes, but customers can also order their car with even lighter and more effective M carbon ceramic brakes, which boast the additional visual highlight of gold-painted calipers.
Lightweight design across the board: Shedding weight in all the right places.
As well as outstanding dynamic qualities, intelligent lightweight design also allows the BMW M4 Convertible to claim exemplary efficiency. Its extensive weight-saving measures produce a curb weight of just 4,055 lbs – around 90 pounds less than its predecessor.
Among the key contributors here are the aluminium front fenders and hood, with lightweight aluminium construction also a feature of the chassis. Extensive use is also made of a material that is both lightweight and extremely stiff, and therefore durable: carbon-fiber-reinforced plastic (CFRP). The new BMW M4 Convertible also features a CFRP drive shaft. The high rigidity and low weight of the CFRP tube mean that the drive shaft can be produced as a single-piece component, without a center bearing. This achieves weight savings of 40 percent over the previous model and a reduction in rotating masses, which in turn results in more dynamic powertrain response.
The CFRP strut brace in the engine compartment is a further example of how all weight-saving measures on these vehicles have also been tailored to the improvement of driving dynamics. Weighing only 3.3 lbs, the strut brace offers superior rigidity to a comparable aluminum component and at the same time plays a key part in the excellent steering response and precision of both vehicles.
The use of carbon is a reminder that BMW is a global leader in high-strength, lightweight CFRP construction, and that it was BMW who brought out the first mass-production vehicle with a body consisting entirely of this material – the innovative BMW i3.
Design: the powerfully expressive face of BMW M.
Viewed from the front, the BMW M4 Convertible stands out most prominently with its powerful contours and a strongly defined three-dimensionality, which lends it a powerfully expressive face. Characteristic design elements leave no doubt that this car is the work of BMW M. There is the modern take on the twin headlight arrangement (with optional LED technology), for example, not to mention the distinctive twin-bar kidney grille with black painted grille bars – which reflect the design of the characteristic BMW M double-spoke wheels and bear the M logo – and the powerfully designed front apron with its trio of large intakes supplying cooling air to the high-performance engine and brakes. Among the other hallmark BMW M design features on display is the characteristic power dome on the hood, which hints at the potential of the brawny M TwinPower Turbo engine and creates space for the intercooler. And the striking exterior mirrors, with their suggested twin-stalk mounts, optimize the aerodynamics of the new BMW M4 Convertible.
The flanks: low-slung silhouette and dynamic lines.
The profile of the M4 Convertible extends the dynamic impression created by its front end. The hallmark BMW proportions of a long hood, long wheelbase, set-back glasshouse and short front overhang are lent further emphasis by familiar M design elements.
Those dynamics-accentuating details include likewise newly designed M gills, which perform both a stylistic and a functional role. Integrated into them are Air Breathers, which team up with the Air Curtains in the front apron to help optimize the airflow around the wheel arches and therefore improve aerodynamics.
The interior design: flawless ergonomics in a sporting ambience.
Climbing into the BMW M4 Convertible, drivers will be greeted by an interior architecture complete with unimpeachable ergonomics and clear driver focus. In keeping with its character, however, the interior fulfils an even more sharply defined sporting brief. To this end, the host of traditional BMW M equipment details includes M door sill finishers, an M driver’s footrest, M gearshift lever, M-design circular instruments with white graphics, M leather steering wheel with chrome trim, color contrast stitching and electroplated-look shift paddles (if the M-DCT gearbox is specified).
The front seats also represent an evocative expression of BMW M’s motor sport genes. Taking visual inspiration from the bucket seats fitted in racing cars, the seats feature a full-size single-piece back panel. This means the construction of the seats is very flat, while the high, width-adjustable side bolsters and low-set seat surface allow an ideal seating position and provide excellent support. Despite their undeniably sporty design, the BMW M sports seats are equipped with comfort-enhancing features including electric adjustment and heating. On the seat surface, the stitching, upholstery segmentation and perforation lend the seats a slim-fitting feel. Illuminated for the first time, the BMW M logo on the seat backrests adds a new and exclusive highlight.
Interior with exquisite materials and motor sport ambience.
The BMW M4 Convertible stands out with an interior that is exclusive and functional in equal measure. For example, the M Sport leather multifunction steering wheel is standard, as are bucket-style M sports seats. New to this generation of Convertible are the available three-temperature neck warmers that allow for comfortable open-air driving at high speeds and low temperatures.
Drivers of the BMW M4 Convertible can look forward to piloting their car from behind a double-spoke M leather steering wheel. The M logo, chrome trim and color contrast stitching are central elements of the cabin’s racing ambience. The M4 Convertible comes standard with a 6-speed manual gearbox, while the 7-speed M Double Clutch Transmission is available as an option. M-DCT allows the driver to change gears using either the selector lever on the center console or the shift paddles mounted on the steering wheel.
Three-piece retractable hardtop. Form and function.
The BMW M4 Convertible offers outstanding everyday driving qualities and a dynamic design, with the top up or down. These seemingly contradictory qualities were already combined in the BMW M3 Convertible, the predecessor that set standards for premium mid-size convertibles. The hardtop of the BMW M4 Convertible features a number of design improvements that reduce noise levels for a much quieter interior ambience. The sound-absorbing headliner also reduces wind noise by up to 2 dB in comparison to the predecessor model.
When the top is up, the luggage compartment has a volume of 13.0 cu. ft. (370 liters) – that is 0.7 cu. ft. (20 liters) more than available in the BMW M3 Convertible. All trunk volumes are based on ECE measures. Even bulky items can be transported with the BMW M4 Convertible. A flat and level storage area can be utilized when the backrest of the rear bench seat is folded down. The load-through feature, which is standard in the US, makes even more space available: Either a wide opening between the rear passenger compartment and the trunk, or a smaller opening, for skis for example, when four people are seated in the vehicle. All it takes is the push of a button to transform a dynamic coupe into an elegant, athletic convertible in a mere 20 seconds. The top can also be lowered when the vehicle is travelling at speeds of up to 18 km/h (approx. 11 mph).
The redesigned windblock is standard in the US. The windblock is now smaller, lighter and easier to use, plus it is more effective than previous variants. When it is not needed, the windblock can be stored behind the rear seat to save space, which is also a new feature. The BMW M4 Convertible also has plenty of space in the trunk, even when the retractable hardtop is lowered. The new convertible offers wider access to the luggage compartment, and an electro-hydraulic loading assistance system raises and positions the folded hardtop in the trunk as needed to ensure maximum utilization of the 7.8 cu. ft. (220 liters) of storage space available.
The loading assistance feature makes sure that there is always ample access to the trunk whether the top is up or down. Two storage compartments on the right and left of the main luggage area are also available for stowing small items when the retractable top is up.
Optional equipment items provide comprehensive driver information.
Needless to say, the BMW M4 Convertible is also available with the wide range of driver assistance systems and mobility services introduced under the BMW ConnectedDrive banner, some of which are already familiar from the BMW M3 Sedan and BMW M4 Coupe. Among the highlights are the new generation of the Navigation System offering extra capability, sharper graphics and 3D elements for the map display, Active Driving Assistant, which warns the driver of a looming collision with a pedestrian or vehicle, the full LED headlights and the intelligent High Beam Assistant.
The optional Head-Up Display comes with additional, M-specific functions such as a gear display, rev counter and Optimum Shift Indicator.
Hall of Fame: Open-top performance for over a quarter century
The new BMW M4 Convertible builds on 26 years of tradition. A Convertible has lined up alongside its two-door Coupe sibling as a firm fixture of the BMW M3 in all four generations.
First generation: the racing car with the soft-top.
The launch of the first BMW M3 in 1986 served primarily to satisfy the homologation requirements for what was then the German Touring Car Championship (DTM). In order to take its place on the grid for this prestigious race series, BMW had to come up with a series-produced version of the competition car and build 5,000 examples of it for sale within a year. The road-spec BMW M3 was created with the demands of motor sport very much at center stage and there were no plans initially for an open-top version. However, after around two years of resistance, BMW eventually gave in to significant customer demand, and the BMW M3 Convertible was unveiled in 1988. It was based on the four-seater BMW
3 Series Convertible and powered by a four-cylinder engine initially producing 193 hp. In 1990, output was increased to 215 hp, enabling the open-top M3 to accelerate to a top speed of 148 mph – making it the world’s fastest four-seater series-produced convertible at the time. The first generation BMW M3 Convertible was not offered in the US.
Second generation: new advances in safety technology.
The powers that be in BMW’s motor sport department – now rechristened M GmbH – had planned an additional Convertible version of the second-generation BMW M3 (launched in 1992 globally and in 1994 in the US) from the outset. Based on the second generation 3 Series Convertible, the BMW M3 Convertible was launched in 1994 with a raft of innovative safety technology on board. For example, the rollover bars of the standard rollover protection system – positioned behind the rear seat head restraints – would spring up in an instant if the car was in danger of turning over, teaming up with the ultra-rigid windscreen frame to protect the passenger compartment. In the US, the second-generation M3 Convertible was powered initially by a 240-hp 3.0-liter inline-six that was later enlarged to 3.2-liters.
Third generation: shining an even brighter spotlight on the car’s sporting character.
In spring 2001, almost exactly a year after the starting gun had been fired on the third generation of the BMW M3, M GmbH unveiled the Convertible variant to join its Coupe stablemate in the line-up. It was identical to the M3 Coupe up to the A-pillar, but a striking beltline gave the open-top model an even broader, more powerful appearance. The BMW M3 Convertible therefore cut a more muscular, broader, more hunkered-down figure than any BMW M3 before it. And it had the bite to back up the bark; hallmark M attributes such as a 333 hp high-revving naturally-aspirated engine, beautifully tuned M suspension, a variable M differential lock and M high-performance brakes enshrined the BMW M3 Convertible as an elite athlete.
Fourth generation: giving the sporting character an even sharper edge.
Less than a year on from the debut of the fourth-generation BMW M3 Coupe and the four-door Sedan that followed a little later, BMW stirred the fires of anticipation among open-air driving enthusiasts with the launch of the BMW M3 Convertible in spring 2008. A 4.0-liter eight-cylinder engine generating 414 hp – and sustaining around 85 percent of its 295 lb-ft peak torque across a rev range of 6,500 rpm – gave drivers of the drop-top four-seater an impressive armoury with which to sate their appetite for sporty, dynamic corner-chasing and relaxed cruising alike.
The new BMW M4 Convertible
The new 2015 BMW M4 Convertible will arrive in US showrooms in summer 2014, in time to capture ideal top-down weather.