BMW M fans have been patiently waiting for the new M3 and M4 to arrive, but the wait is nearly over. BMW has confirmed the new M3 and M4 will finally break cover this September, marking the start of a new generation for the iconic performance sedan and coupe. After we were given a better look at the new BMW M4 last week, our spies have caught the 2021 BMW M3 being tested on city streets as development reaches the final stages.

There's less camouflage than previous prototypes, giving us a closer look at the car's gigantic grille carried over from the controversial BMW 4 Series. While this will help distinguish the M3 from its regular 3 Series sibling, this new design direction has already proven to be divisive for the 4 Series, so we're expecting the 2021 M3 to face a similar backlash.

Elsewhere, this BMW M3 prototype is sporting production headlights and taillights. All the usual visual cues that differentiate BMW's M models are also clear to see, from the larger air intakes and wider fenders, to the quad exhaust system and larger wheels.

While not everyone is going to love the 2021 BMW M3's bold new look, enthusiasts should have nothing to complain about in the performance and handling department. Compared to its predecessor, the next-generation BMW M3 will boast a significant performance boost. Catering for purists, the base model will produce 480 hp (49 more hp than the previous model), which will be sent to the rear wheels through a six-speed manual shifter.

Upgrading to the Competition version will increase the output to 510 hp (a 60 hp gain over the outgoing M3 Competition) but the six-speed manual will be replaced with an eight-speed automatic. An AWD variant of the M3 Competition will also be available after launch. The M3 Competition won't be the hottest variant either, as spy shots have already confirmed the new BMW M3 CS is in development.

Regardless of which version you choose, power will be sourced from a twin-turbocharged 3.0-liter straight-six engine, which also powers the BMW X3 M and X4 M SUVs. Also expect the new M3 to be even more satisfying to drive, as BMW promises the suspension, springs, dampers, and braking technology will be significantly improved.