BMW is keen to point out the differences in size between the previous-generation 3 Series coupé and this 4 Series, but it makes less of a fuss about the variations between the current 3 Series and 4 Series.
Truth is, they’re not so different at all. The 4 Series is just 14mm longer, and the same amount wider, than the saloon on which it’s based, but it’s 62mm lower. Most significantly, the wheelbase is unchanged at 2810mm. It’s a set of numbers that puts the 4 Series squarely in Audi A5 territory; in fact, there’s just 2mm of length between the pair.
The mechanical layout is straight from the saloon, too, so it’s a steel monocoque and body with a smattering of aluminium and plastic to keep the weight down. BMW says the 4 Series is up to 25kg lighter than its predecessor; a 440i we tested tipped the scales at 1640kg, which is reasonable for a car of this size with the biggest of available engines. Its weight was pleasingly central, too, at 51 percent front, 49 percent rear.
The core of BMW's rear-wheel-drive 4 Series comes with the choice of six engines. The petrol options options comprise the 420i and 430i, which are both turbocharged 2.0-litre fours making 181 and 248bhp respectively, and the 440i with its 321bhp turbocharged 3.0-litre six. The latter is a particularly potent piece of kit. It offered 7bhp less power than the previous Audi S5 - although that deficit has now stretched to 28bhp - but it only has to push that oomph through its rear wheels.
Diesel choices are, unsurprisingly, likely to be more popular, but there are slightly fewer options than in the 3 Series range. It kicks off with the best seller, the 420d. With outputs of 181bhp and 124g/km of CO2 it's the model destined to be the one most frequently found on the motorways, and the one that'll find favour with company car drivers.