What is it?
The BMW naming convention music has stopped once again, and in this year's scramble for a seat; the M235i has been elbowed aside by the new M240i and been made to sit in the corner. But in truth, there is more to this replacement than just a bigger-numbered badge affixed the compact two-door coupé's bootlid.
In the same vein as the new M140i hatch we drove only recently, BMW has fiddled its twin-scroll turbocharged 3.0-litre straight six petrol engine to produce an extra 14bhp at 5500rpm, bringing the new total to 335bhp, and it now offers 369lb ft between 1520 and 4500rpm - some 37lb ft more twist.
Naturally, the M240i is now quicker in a sprint, our manual car officially capable of 0-62mph in 4.8sec, 0.2sec faster than the M235i. And in yet more Bavarian wizardry, fuel economy is also improved by up to 7%, meaning the manual version now returns 36.2mpg on the combined cycle and emits 179g/km of CO2.
The final headline changes are a new rev-linked vibration damper (on the automatic version only) that aids engine refinement between shifts under load, and a new acoustic bonnet shield that's designed to filter out other noises to make the engine sound purer.
What's it like?
With no chassis changes as part of this revamp, the main focus is on the M240i's more powerful engine, and what an engine it still is. Manufacturers talk about pull "from almost any gear, at any revs" but, well, you get the idea: you rarely find yourself hurriedly snatching a lower gear in need of a higher crank speed here. The straight six has absolutely no issue being at the other end of the dial, either, and neither will you; the noise is deep, purposeful and muscular.
If there are any problems with the performance, it's perhaps that there's a little too much. We've said it before, but the M240i's rear tyres are quite easily overwhelmed on wet roads, while BMW's manual shift isn't the slickest out there. There's a purpose to its shifts, yes, but it requires more precision than should be necessary when there are other things on your mind. Such as, "It's raining and the rear axle moves about a bit, doesn't it?"
Still, keep the M240i dialled to Comfort or Sport mode and the traction control is quick to step in and save the day. Only Sport Plus really demands your fullest attention when the going gets soggy.
In the right conditions, though, Sport Plus is exactly where you'll want to be. The throttle, steering and optional adaptive dampers are primed for action and all feel their best in this mode, ensuring the M240i remains every bit as poised, agile and communicative as its predecessor. It falls only just short of the handling benchmark set by the Porsche 718 Cayman, which keeps it body better vertically planted across undulating, camber-ridden roads and steers with a touch more linearity.
But the M240i's marginally softer approach, and in particular the adaptive dampers in Comfort mode, makes it the more rounded prospect if you do as much cruising as you do cornering. Dialled right back, the engine settles down and the suspension is allowed to breathe enough that everything from sleeping policemen to high-frequency ruts never intrude.