BMW 4 Series Coupe: lighter, faster two-door revealed

Officially revealed, the BMW 4 Series Coupe is longer, wider, lower, up to 45kg lighter and 60 per cent stiffer than its 3 Series Coupe predecessor.

BMW reinforces the reasons for the name change, saying that the new 4 Series Coupe �??emphasises not only its stand-alone design, but equally an even greater technical differentiation from its BMW 3 Series cousins�?�.

Compared with the current 3 Series sedan, the BMW 4 Series Coupe sits a full 67mm lower, and a roll centre reduced by 19mm is the lowest of any current BMW. The 4 Series Coupe is also 14mm longer and wider, with wider front and rear tracks �?" extending by 14mm and 22mm respectively.

BMW calls the 4 Series Coupe design �??extremely width-accentuating�?�. The rear wheelarches are now the widest point of the car, the twin-split kidney grille is larger than before, and the front air dam is positioned lower on the front bumper and has a wider reach across it.

Nestled on the far sides of each air intake are aerodynamically motivated �??Air Curtains�?� that improve air flow around the front wheels, while at the rear of the front wheelarch �??Air Breathers�?� then deflect air out of the arch to reduce resistance. Each are claimed to help reduce fuel consumption. The 4 Series Coupe has an aerodynamic rating of 0.28Cd.

Inside, the BMW 4 Series closely mirrors its 3 Series sedan cousin, with the exception of wider front doors and a redesigned iDrive dial that is now a touch controller. Frameless doors and an automatic seatbelt feeder are 3 Series coupe trademarks that carry over. The 4 Series Coupe also debuts Driving Assistant Plus, which warns the driver of a potential collision with a pedestrian.

A 40:20:40 split folding rear backrest is an option, but a centre ski port is standard.

As with the 3 Series sedan, the 4 Series Coupe is available with three interior design packages called �??lines�?? �?" Modern, Luxury and Sport. An M Sport package is also available, with M Sport suspension and larger 19-inch wheels. Electro-mechanical power steering is standard, with a variable-ratio Sport steering optional along with adaptive dampers.

Three engines are available at launch, all borrowed from the 3 Series Coupe, and each available with a six-speed manual transmission or an eight-speed automatic.

All get stop-start technology, while the auto debuts a �??coasting�?? mode to help reduce fuel consumption, which decouples the engine from the transmission when cruising off the accelerator between 50 and 160km/h.

The 420d Coupe uses a 2.0-litre turbo-diesel four cylinder pproducing 135kW of power at 4000rpm, and 380Nm of torque between 1750-2750rpm. Claimed consumption is 4.7L/100km combined, and the engine pushes the 1450kg two-door to 100km/h in 7.5 seconds.

Middle-grade 428i Coupe gets a 2.0-litre turbo petrol four cylinder with 180kW at 5000-6000rpm and 350Nm between 1250-4800rpm. A 5.9 second 0-100km/h sprint and 6.3L/100km (auto) or 6.6L/100km (manual) fuel usage makes it quicker and more frugal than the 328i sedan.

Flagship for now, the 435i Coupe utilises a 3.0-litre turbo petrol six-cylinder that makes 225kW at 5800-6000rpm and 400Nm from 1200-5000rpm. While the 0-100km/h sprint for the rear-drive version takes 5.4 seconds, the not-for-Australia all-wheel-drive model reduces that time to just 4.9 seconds �?" as quick as the outgoing V8-engined BMW M3. The 1510kg rear-drive 435i drinks 7.3L/100km as an automatic, or 7.9L/100km with a manual transmission.

All 4 Series Coupe models are 60 per cent stiffer than the previous 3 Series Coupe, despite being up to 45kg lighter.

Although the chassis basics mirror the 3 Series sedan, according to BMW the 4 Series, in addition to its lower centre of gravity, has had �??its springs and damping, axle kinematics and elastokinematics �?� � tailored precisely to the hugely engaging character of the new Coupe.�?�

The BMW 4 Series will make its official public debut at the Frankfurt motor show in September, before going on sale here early 2014. A BMW M4 Coupe will follow later next year to usurp the 435i Coupe�??s position as the sports range topper�?�

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