At the introduction of a turbocharged motor, the way power is delivered is as important as the raw figures.
There is no drama with the latter; the M4 is a ridiculously fast car, with launch control ensuring that it passed 60mph from rest, in our hands, in 4.1sec, and 100mph in 8.8sec.
Despite a claimed 155mph limited top speed, it took only 25.2sec to hit 160mph on MIRA’s mile straight, passing a standing quarter mile in 12.3sec and at 120.9mph on the way. That’s only a fraction slower – a single tenth over a quarter mile – than a 2012 Porsche 911 GT3 RS.
Power delivery is a different question entirely. BMW has fitted two relatively small turbos – each working on three cylinders – to ensure they spool up quickly.
The engine is canted to clear the bonnet and has a sophisticated oil return system to avoid starvation and thus cope with the track-day running that is so essential to enjoying this car’s capabilities.
In practice, the turbos may be small, but they do have an effect. No matter how minimal the lag is, there’s no question that this is a less responsive engine than a naturally aspirated one and therefore comes with less urgency to a throttle prod than any M3 to date.
That fact appears harsh when written down, because on the road, for the most part, it doesn’t matter. Yes, there is the tiniest delay between asking for a lot and getting it, but BMW has still crafted an engine that is better than any of its turbocharged peers. It is silky smooth, revs commendably high and, at higher revs, responds as closely to natural aspiration as it’s reasonable to expect.