BMW 3 Series M3 Convertible M DCT

Overall rating

The final piece of the M3 jigsaw – BMW claims there is not enough demand for a Touring model – the M3 Convertible is the first BMW M model to feature a folding hard-top roof. It's also the first to be available with the manufacturer's new twin clutch gearbox, raising the interest for those waiting for it to be rolled out further.

Now in its fourth generation, the BMW M3 has always been a showcase for the German manufacturer's new technology. This time it's the seven-speed, twin clutch M DCT gearbox that's being unveiled, capable of improving both on road performance and fuel economy by providing a constant connection between the engine and rear wheels. Powered by the same 4.0-litre, 420bhp V8 as the Coupe and Saloon models, the M3 Convertible is engineered to offer the same thrilling on road performance even with the roof down.

Bristling with technology including the new gearbox with Drivelogic – allowing it to be fine-tuned to individual driver's tastes – and the impressive folding roof mechanism, the M3 Convertible also features technology from BMW's Efficient Dynamics range including brake energy regeneration and a shift indicator on manual models for more fuel efficient driving.

The M3 Convertible's showpiece roof can be lowered in 22 seconds and is stored in the boot with three sections stacking on top of each other. The model retains its muscular looks even with the roof down and with the roof up it provides the refinement and driveability of the Coupe or Saloon.

To ensure none of the M3's legendary handling and performance is lost, the Convertibles chassis has been reinforced and the body lightened – even the tyres have shed weight so as not to blunt the car's performance. Naturally, as part of the range-topping M3 line-up, the Convertible is fully equipped inside with a luxurious interior and a wide array of toys and equipment.

Our verdict on the BMW 3 Series M3 Convertible M DCT

Every bit a performance car, and offering top-down motoring, the M3 Convertible is a worthy addition to the range. The M DCT transmission adds a third dimension to the model: high performance coupe, summer cabriolet and now relaxed automatic cruiser. Drivers suitably unencumbered and wealthy enough to take advantage of the model may be few and far between, but the lucky few will find it a rewarding and exciting car to own.

Costs

The M3 Convertible is not a cheap car to buy, even less so once additional options such as the M DCT gearbox have been added. It's also likely to incur high insurance costs, while its thirst for fuel will mean running costs are not cheap. It offers a significant amount of luxury and performance for the money, but requires a considerable outlay to own.

Space and practicality

The M3 Convertible is a fundamentally impractical car, but efforts have been made to make it useable day-to-day. The boot will carry a respectable load with the roof up and the rear seats can be folded flat to uncover a hatch that offers a portal to the boot, making it possible to carry longer items. The cabin is somewhat cramped with excessive levels of equipment appearing to take up a lot of room. Rear passengers will struggle for legroom, but headroom is surprisingly abundant.

Controls and display

Considering the amount of equipment present, BMW has done an excellent job of providing a sensible and ergonomic control and switchgear layout. Many functions are controlled through the menu-based iDrive, which takes time to master. The rest of the controls are sensibly placed and items like the M DCT gear lever are neatly styled. The displays are good, but the digits on the speedo are on the small side. The shift lights incorporated into the rev counter are a neat idea.

Comfort

The M3 Convertible is very comfortable regardless of the speed it's driven at. The seats are electrically adjustable, shapely and supportive and all mod cons are catered for. It's also extremely refined and, although the engine and exhaust note is a welcome constant presence, wind and road noise is kept out by the metal roof. Even with the roof down, the car can be driven at high speed without driving the occupants to distraction

Car security

The hard-top roof provides the Convertible model with all the security of the Coupe and Saloon, but there's a Category One alarm and immobiliser included, too. The contents of the boot are always out of sight and additional covered storage can be found inside the cabin.

Car safety

The M3 Convertible's brakes are a basic design but highly competent. They, like hugely powerful drivetrain, are governed by electric aids packaged as Dynamic Stability Control and incorporating Dynamic Stability Control traction control, corner brake control, electronic brake force distribution and engine drag torque control. There are also copious airbags should the worst happen and two stage brake lights to warn following drivers of problems.

Driver appeal

As with the Coupe and Saloon, the M3 Convertible is a formidable performer with amazing outright speed and acceleration. The adjustable twin clutch manual is a real boon, enabling the car to be comfortably driven in fully automatic mode or capable of providing neck snapping shifts on track. The handling is awe-inspiring, with the stiffened chassis suffering the bare minimum of scuttle shake with the roof down. The only down side is steering that feels unnaturally heavy and lacks the feedback of some of the M3's sports engineered rivals.

Family car appeal

The M3 Convertible is far better suited to the affluent driver unhindered by children. Removing youngsters and child seats from the rear would quickly become tiresome and it would be virtually impossible to take a family holiday with the limited space available.

First car appeal

Powerful, fast and expensive, the M3 Convertible would be a poor choice for a first car. Although easy to live with, the incredible on road performance would soon land novice drivers in trouble. All but the wealthiest would find it very difficult to insure.

Quality and image

The M3 has near super car appeal. Whether the Convertible version raises or lowers that is a matter of individual taste, but the impressive roof mechanism attracts plenty of attention regardless. The M3 Convertible benefits from the utmost build quality and precision craftsmanship nose to tail.

Accessibility

Access to the rear is the main bugbear for the M3 Convertible. Naturally, the two-door layout makes it necessary to fold the front seats forward and to stoop in, with the roof in place at least. It also has a low-slung driving position, which makes it less easy to get in and out of than a regular road car. The boot offers reasonable access to the rear, unless the roof is stowed in which case items need to be extracted from beneath the folded panels.

Stereo and ICE (In car entertainment)

Sat-nav is standard on the M3 Convertible, as is an MP3 and DVD compatible CD player plus radio with auxiliary input. The system is largely controlled through the iDrive system and favourites buttons are also included for extra ease of use. A crystal clear 8.8-inch colour screen relays info and entertainment, while sound quality from the speakers is excellent.

Colours and trim

A total of eight exterior colours are available, and the beefy styling means that the M3 Convertible looks particularly good in bolder shades. There's also a healthy line-up of colour choices for the leather interior. 18-inch alloys are standard and the M3 Convertible receives top-level brushed metal trim inside too, all crafted to the usual impeccable BMW standards.

Parking

Rear parking sensors are standard which is a big help as, although visibility is great with the roof down, the high shoulders restrict the view of the bulky rear when reversing. Even so, the view from the rear is considerably better than in some hard-top cabriolets. The turning circle is good, making tight manoeuvres manageable.

Spare wheel

Tyre sealant kit fitted as standard.

Range information

Petrol engine options – 2.0-litre (143hp); 2.0-litre (170hp); 3.0-litre (218hp); 3.0-litre (272hp); 3.0-litre (306hp) ;4.0-litre (420bhp). Diesel engine options – 2.0-litre (143hp); 2.0-litre (177hp); 3.0-litre (197hp); 3.0-litre (231hp); 3.0-litre (286bhp). Transmission options: six-speed manual gearbox, six-speed automatic gearbox with manual over-ride, seven-speed M DCT twin clutch automatic gearbox with paddle shift. Trim levels: ES, SE, M Sport, M3.

Alternative cars

• Audi A4 Aluminium V8 powered RS4 Cabriolet is closest rival
• Mercedes Benz CLK-Class CLK63AMG cabriolet boasts impressive V8 performance
• Jaguar XK Stylish two-plus-two convertible has V8 power, too
• Aston Martin Vantage Only two seats for Vantage Roadster, but a glorious sounding V8