BMW 3 series convertible hardtop arrives

The 3 Series convertible arrives less than a month after the coupe, launch in Australia and more than 12 months after BMW’s highest selling sedan range.

It’s the first time BMW has gone for a folding hardtop roof, which comes after the August release of Mazda’s well-received folding hardtop for its MX-5 Roadster Coupe.

The lightweight steel roof retracts in three pieces automatically, or via a remote control as standard.

BMW has claimed a design triumph in maintaining the iconic characteristics of a coupe despite the folding hardtop.

"Usually with retractable hardtops the roof is in a wedge or dome shape so it can fold into the boot," said a BMW spokesman. "But we’ve kept the key hallmarks of BMW design cues."

These include a roof that remains parallel to the ground. A flat boot lid. And a steep-angled, straight front windscreen.

Radio and GPS aerials are concealed within the body work, including the side panels for when the roof is down, or in rear window when the roof is closed.

The company boasts that this 3 series has the highest torsional stiffness offered in a BMW convertible, which measures the degree to which a body twists under stressed driving conditions.

The less twist, the better the handling, and while all sports cars traditionally have a high degree of rigid torsion in their body, convertibles often sacrifice the rigidity gained by a roof.

The 3 Series hardtop is said to keep the new BMW convertible in the same rigid torsion zone enjoyed by traditional sports cars.

The 335i and 325i engine from the current coupe range would be used in the 3 Series convertible, with prices to be announced closer to the March onsale date.

FAST FACTS

BMW 335i Convertible: straight-six petrol engine with Twin Turbo technology and direct fuel injection (High Precision Injection), 2,979 cc engine capacity, 225 kW/306 hp max output, 400 Nm/295 lb-ft max torque, acceleration 0–100 km/h in 5.8 sec, top speed 250 km/h, average fuel consumption 9.9 litres/100 km.

BMW 330i Convertible: straight-six petrol engine with direct fuel injection, 2,996 cc engine capacity, 200 kW/272 hp max output, 320 Nm/236 lb-ft max torque, acceleration 0–100 km/h in 6.7 sec, top speed 250 km/h, average fuel consumption 8.1 litres/100 km.

BMW 325i Convertible: straight-six petrol engine with direct fuel injection, 2,996 cc engine capacity, 160 kW/218 hp max output, 270 Nm/199 lb-ft max torque, acceleration 0–100 km/h in 7.6 sec, top speed 245 km/h, average fuel consumption 7.9 litres/100 km.

BMW 320i Convertible: straight-four petrol engine with direct fuel injection, 1,995 cc engine capacity, 125 kW/170 hp max output, 210 Nm/155 lb-ft max torque, acceleration 0–100 km/h in 9.2 sec, top speed 220 km/h, average fuel consumption 6.7 litres/100 km.

BMW 330d Convertible: straight-six diesel engine with all-aluminium crankcase and latest-generation common rail fuel injection, 2,993 cc engine capacity, 170 kW/231 hp max output, 500 Nm/369 lb-ft max torque, acceleration 0–100 km/h in 7.1 sec, top speed 245 km/h, average fuel consumption 6.9 litres/100 km.

Interior features

• Four full size seats (single rear seats separated by centre console which extends back).
• Max. luggage capacity of 350 litres.
• Sun reflective technology.
• Leather upholstery.

Safety features

• Frontal, head, thorax airbags.
• Belt latch tensioners.
• Belt force limiters.
• Senor-controlled safety electronics (rollbars move up automatically when required behind the rear seats).