BMW 3-Series Convertible

The fourth generation of BMW's 3 Series four-seat convertible made its world debut at the North American International Auto Show (NAIAS). A new dimension in the world of motoring comes with the introduction of a retractable hardtop for the first time in a BMW. Made of lightweight steel, the three-piece roof opens in just 22 seconds and folds smoothly into the rear compartment of BMW’s newest convertible. The new roof structure ensures a lower level of noise even at high speeds while the ultra-stiff platform provides extreme torsional strength for rigidity and incredible handling inherent to all BMWs.

The new BMW 3 Series Convertible retains all the elegance and unique style that is characteristic of the 3 Series with the top either open or closed. The long and sleek hood, low shoulder line and the broad-shouldered rear end make the new BMW 3 Series Convertible unmistakable from any angle. And with the new retracting hardtop, it offers performance, comfort, safety, and value unique in its segment.

Following the Sedan, Sport Wagon and Coupe, the new 3 Series Convertible is the fourth variant of the highly successful BMW 3 Series line-up. Despite the familial resemblance borne out in many design features typical of the brand, the new Convertible is truly unique. Looking at the front end of the car, all similarities to the BMW 3 Series Coupe are only from the A-pillar forward. The sporting style of the new Convertible starts at the contours of the long and low hood as well as the special design of the front air dam and headlights. The distinctive BMW kidney grilles stand out more upright than the surrounding areas and surfaces.

The side view of the car is dominated by the horizontal shoulder line which gives the new 3 Series Convertible particular style and elegance. The large wheel arches add sporting and dynamic flair from every angle. The sleek and dynamic look of the new 3 Series Convertible is further accentuated by the contour line that runs level with the door handles. A sill-line at the lower edge of the doors continues all the way into the air dams at the front and rear.

This interaction of the car’s lines and carefully-modelled surfaces provides a striking three-dimensional effect guiding not only more light, but also the eye of the beholder to the area around the car’s rear axle. This effect is indeed intentional, with the optical impression created in this way reflecting the actual driving experience as the new 3 Series Convertible, like all BMWs, features rear wheel drive for outstanding performance on the road.

The rear view of the car is equally sporting and elegant: particularly with the roof down, the new BMW 3 Series Convertible also looks low and wide from behind. And while the contour line ends in the rear light clusters at each side, the shoulder line extends around the entire rear section. The rear tail lamp assemblies are split into two sections and extend all the way into the lid of the luggage compartment. Horizontal LED light rods ensure a striking look at night, while the third brake light is integrated into the aerodynamically-designed spoiler edge on the decklid.

Two versions will be available in the US. The powerful 335i Convertible features BMW’s newest inline six-cylinder engine with twin turbochargers and an intercooler for 300 incredibly flexible horsepower, thanks to high precision direct fuel injection with piezo injectors. The 328i Convertible features a 230-hp 3.0-liter inline six-cylinder engine with Valvetronic technology and aluminum/magnesium construction.

The more sporting version of the new 3 Series Convertible, the 335i, is powered by the world’s first inline six-cylinder with Twin Turbo and High Precision Direct Injection technology and an all-aluminum crankcase. Rated at 300 hp at 5,800 rpm and 300 lb-ft of torque at 1,400 – 5,000 rpm, this 3.0-liter engine offers cutting-edge performance thanks to the theories behind BMW’s Efficient Dynamics. Using high-tech materials allows the engine to be a lightweight performer, which helps BMW achieve near 50/50 weight distribution on this and all of its vehicles. Low inertia turbocharger internals and high precision direct fuel injection makes turbo lag nearly non-existent as peak torque starts at a mere 1,400 rpm. High precision direct injection is also ideal for lean burn operation. In the lean burn mode, various intercepting layers of the fuel and air form within the combustion chamber. The fuel/air mixture is therefore particularly rich and ignitable only in the direct vicinity of the spark plug and once ignite,the flame travels to the leaner layers further from the spark plug for a clean, smooth and consistent combustion process. Redline is still an impressive 7,000 rpm and compression ratio is 10.2:1. Typical of a BMW engine are incredible smoothness, fast-revving response and refined power at all engine speeds.

The BMW 335i Convertible accelerates to 60 mph in just 5.5 seconds for the six-speed manual, and in 5.7 seconds for the six-speed Steptronic automatic transmission. Top speed is electronically-controlled to 130 mph and on vehicles equipped with the Sport Package, top speed is governed at 150 mph.

The 328i Convertible is equipped with a the 3.0-liter inline six-cylinder engine that delivers 230 smooth horsepower at a peak of 6,500rpm and 200 lb-ft of torque at 2,750 rpm. Featuring BMW’s innovative Valvetronic engine system, which eliminates the conventional throttle body for throttle control, efficiency and power are available over a broader range for silky-smooth operation. The magnesium/aluminum block is a perfect example of BMW Efficient Dynamics where lightweight technology is at work, making the 328i unique against its competition. The electric engine coolant pump also demonstrates one of the many examples where efficiency can be felt at the accelerator pedal. Speaking of which, acceleration from 0 to 60 mph comes in a spirited 6.7 seconds for the six-speed manual and in 7.2 seconds for vehicles with the Steptronic six-speed automatic transmission. Like the 335i, the 328i is limited to 130 mph or 150 mph if equipped with the Sport Package.

A thoroughly enhanced six-speed automatic transmission is available as an option on both models to meet the greatest demands for comfort and performance. A quicker and more responsive hydraulic control system, together with an innovative new torque converter and significantly enhanced control software ensure reaction times that are 40% faster than conventional automatic transmissions. In addition, gear change timing has been almost halved. The torque converter clutch connects the engine more directly to enhance performance, response and fuel economy.

Should the driver wish to control the sporting character of the transmission directly, the optional paddles on the steering wheel provide direct selection of the gear when in manual mode. Because the gearshift paddles can be activated directly at any time, even if the gear selector lever is in Drive, this manual gearshift function always provides extremely spontaneous performance. Shift paddles are an available option when ordered with automatic transmission and Sport Package.

With power being transmitted to the rear wheels, the rack-and-pinion steering remains free of drive forces. Optional Active Steering varies steering ratio as a function of road speed for higher steering ratio at the same steering wheel angle at low speeds than at high speeds. This enables the driver to control the car even more smoothly and with minimal effort, while remaining precisely on course at high speeds in the interest of maximum safety.

Featuring a double-pivot McPherson strut-type aluminum suspension in front and a five-link independent rear suspension, the new BMW 3 Series Convertible boasts the most advanced underpinnings in its class. Further advantages are the low center of gravity, well-balanced axle load and special damper set-up helping to give this outstanding new convertible its impressive dynamic driving qualities.

The standard 17-inch alloy wheels run on 225/45R17 tires with runflat technology. Even with a complete loss of pressure in one tire, the vehicle can continue to be driven for up to 150 miles at 50 miles per hour to get to the nearest service station. BMW’s new Tire Pressure Monitor watches the pressures in each tire and will warn the driver as soon as the pressure drops more than 25 percent below the optimum level.

Source: BMW press

Gallery: BMW 3-Series Convertible