The new-generation engine seems more akin to a laser scalpel than the lump-hammer you’ll find in some rivals, but it seldom fails to make the X4 M a fast car, either on road or track. It doesn’t gush with vocal charisma like an AMG V8 or Alfa Romeo V6, but it has plenty to be going on with. It feels very responsive under your foot and about as smooth, flexible and linear in its power delivery as any turbocharged engine of its kind.
It’s an engine to be admired in gear, under load and in use, in other words, at both middling and high revs, rather than when burbling away at a halt or cracking affectedly on the overrun. And you interact with it through an eight-speed torque converter automatic gearbox that’s good enough to seem like an improvement on BMW M’s old seven-speed dual-clutch unit in almost every way that matters.
The X4 M's ride and handling can be tailored and adapted a little bit using the familiar mode selector buttons for steering, adaptive damping and engine calibration – although not as widely or as effectively, it must be said, as some fast SUVs allow. If you're anything like us, you’ll spend most of the miles with the suspension and steering dialed down and the powertrain dialed up. That’s because the ride is a bit short, tetchy and given to thumping even with the dampers in Comfort mode, while the variable-ratio steering picks up a bit too much weight and pace in its more aggressive settings to feel either fluent or intuitive.
The X4 M doesn’t quite have the sense of compactness and agility necessary to make it easy to thread quickly down a narrow country road, but it flows well enough along smoother, wider ones and feels flat, taut and controlled in its bigger body movements, with an assured and commanding level of grip.
To drive it to the limit of grip on a circuit is to take it to a place that most owners almost certainly won’t, but when you do, you’ll discover that the car’s body control survives well. It only begins to run out of composure under extremes of lateral load and in its firmer damping modes, when it can begin to hop on its outside rear wheel and feel slightly untidy and unforgiving if you seek to adjust the car's attitude.