Next BMW M4 leaked

The all-new BMW M4 has been leaked online ahead of its official launch later this year.

The images, posted on Reddit by

Like the recently revealed G22-series 4 Series Coupe on which it's based, the 2021 BMW M4 will be punctuated by a daring new 'big mouth' grille. But it's clear from our first glimpse that, if anything, it will wear an even more prominent take on the divisive front-end design that is dominated by a pair of oversized kidney grilles said to be inspired by the original 1930s 328 sports car.

They're tough to see here, but earlier spy shots also suggested the M4 will also come with swollen front and rear wheel-arches, reflecting an increased track and a more muscular stance.

The next BMW M4 will also bring some big aero changes over the standard 4 Series.

Witness the larger air intakes that flank the grilles and the scooped openings below the outer edge of the headlights. Those are designed to vent air around the front wheels to reduce lift over the front axle.

Early spy shots of the rear-end already indicated the last car's quad exhaust outlets will return, as will a large diffuser.

Look closely at the most recent images and it appears the previous car's carbon-fibre roof panel is missing, replaced with what looks like a body-coloured panel.

It's not known if the car spotted here features a painted carbon roof, or if the lightweight composite panel will be reserved for a faster version to come, like a replacement for the BMW M4 CS.

Under the bonnet, we already know that both the M4 coupe and M3 sedan will be powered by an updated version of the S58 twin-turbocharged 3.0-litre inline six-cylinder that will produce around 353kW.

As well as more power, BMW M has overhauled the engine to make it more engaging and willing to rev beyond 7000rpm – a criticism of the current S55-powered cars.For the first time, the flagship 4 Series coupe, sedan and upcoming convertible will be joined by a four-door coupe badged the M4 Gran Coupe.

Both the 2021 M3 and M4 will also be available in more powerful Competition form, producing about 374kW – 6kW more than the outgoing M4 GTS.

Both the base M cars and the M3/M4 Competition will generate 600Nm – 50Nm more than before, and deliver peak pulling power from a low 2600rpm.

Remarkably, despite pumping out more power and torque, the new engine has been future-proofed for ever-tightening emission regulations by incorporating new twin Otto particulate filters.

Helping achieve more power and lower emissions are new mono-scroll turbochargers that are combined with BMW M's next-generation Valvetronic variable valve timing and Double Vanos variable camshaft profile.

There are also reports that the compression ratio has been reduced from 10.2:1 to 9.2:1.

Despite producing more power than the previous M4 GTS, the new generation of M cars do without water injection – but that could return for the successor to either the current M3/M4 CS or the M4 GTS.

There's still no official confirmation from BMW about what transmission the new M cars will come with, but it's thought at least one version will get the M5's eight-speed automatic and xDrive all-wheel drive with M-Dynamic rear-drive mode.

To the relief of enthusiasts, a lower-powered entry-level model will also be offered with a six-speed manual gearbox and rear-wheel drive.