BMW does the math: The 4 Series Convertible is the 3 Series Convertible + 1

BMW has finally given up the charade and released the full photos and production specs of the 4 Series Convertible just a few short days after accidentally letting images of the new convertible leak in a German market accessory booklet.

Without the silly bike rack strapped to the back, the new 4 Series ‘Vert looks very good indeed. While untrained eye might think the BMW 4 Series Convertible is simply a rebadged 3 Series Convertible, nothing could be further from the truth.

The new 4 Series Convertible is actually one inch longer, 1.7 inches wider, and sits much closer to the pavement than its predecessor, the 3 Series Convertible. Here’s how BMW puts it, “The new 4 Series Convertible represents something more than its BMW 3 Series cousins – 3+1, if you will.” Thanks for the arithmetic help, there, BMW.

Unlike the European market, which will see a whole slew of engine options, the U.S. 4 Series Convertible will only be offered in 428i, 428i xDrive, and 435i. Just like their hardtop brother, the 428i will be powered by a TwinPower Turbo 2.0-liter four-cylinder engine and the 435i will have the multi-award winning TwinPower Turbo 3.0-liter inline six bolted under its hood.

The redesigned power-folding hardtop will stow away in 20 seconds up to speeds of 11 mph. In addition, the roof now includes a sound-absorbing headliner, which makes for much quieter motoring with the top up. When the top is up, the 4 Series Convertible boast a drag co-efficient of 0.28 and when the top is down, it’s 0.33. What does that mean to you? Well, to put that into perspective, the all-new Mercedes-Benz CLA has a drag co-efficient of 0.23, which is five less than the 4 Series Convertible.

And what does that mean? Well, the 4 Series Convertible is pretty slippery in the air. The CLA is just more slippery. OK never mind. It doesn’t really matter that much; it’s just something that automakers like to brag about.

The new 4 Series Convertible is offered in three more sub-models, beyond the 428i and 435i. Buyers can spec their 4 ‘Vert with a Sport Line, Luxury Line, or M Sport options package.

Sport Line adds gloss black trim bits to the exterior, a sport suspension for rear-drive models, 18-inch or optional 19-inch rims, black exhaust tips, sport steering wheel, and red accents on the interior.

The Luxury Line adds chrome and black accent bits to the exterior, the same 18- or optional 19-inch wheels, leather seating, and Ash Grain anthracite fine wood trim surfaces, and a Pearl Gloss Chrome metal inlay.

M Sport adds an M aerodynamic package, including numerous body components (front apron with large air intakes, rear bumper with diffuser, side skirts), and high-gloss Shadow Line trim. On the outside, Estoril Blue Metallic paint is available only with M Sport on the 4 Series Convertible. And for the true ‘Ultimate Driving’ experience, BMW adds a leather M Sport steering wheel, M Sport suspension (rear-wheel drive models only) and M Sport Brakes.

What will this Teutonic, drop-top motoring experience cost you? The 2014 BMW 428i Convertible will start at $49,675, and the 2014 BMW 435i Convertible will fetch a starting price of $55,825.

Want to know what it might be like to drive? Check out our first-drive report on the 2014 BMW 4 Series.