UPDATE, 19 April 2021, 11:30am: BMW Australia has confirmed first deliveries of the M3 and M4 Competition xDrive will commence in the fourth quarter of 2021 (October to December inclusive).
Our original story continues below.
19 April 2021, 9:45am: The 2021 BMW M3 and M4 Competition xDrive have been revealed – bringing a long-awaited all-wheel-drive system to the brand's high-performance mid-size cars – ahead of their local launches expected later this year.
Powering the flagship M3 and M4 is the same 375kW/650Nm 3.0-litre twin-turbocharged 'S58' inline-six as the rear-drive Competition variants launched in local BMW showrooms in recent months, paired to an eight-speed torque-converter automatic transmission.
However, whereas the existing cars drive the rear wheels, the xDrive models route power to all four corners – firsts for both nameplates – through a downsized version of the switchable M xDrive all-wheel-drive system fitted to the larger M5 super sedan.
The added grip enables 0-100km/h sprint times of 3.5 seconds – four-tenths quicker than the rear-wheel-drive models' 3.9-second claims, but matching the next-generation Mercedes-AMG C63's rumoured 3.5-second sprint time, and two-tenths down on the all-electric Tesla Model 3 Performance.
Like its larger M5 sibling, the M3 and M4's M xDrive systems offer a choice of three modes – 4WD, 4WD Sport and 2WD – with the lattermost disconnecting the front axle and disabling stability control to drive the rear wheels only.
4WD Sport engages both axles but sends a far greater percentage to the rear for "sharper agility" and "to execute controlled drifts", while the default 4WD setting retains a rear-biased torque split, but focuses on maximising traction in slippery conditions.
The all-paw system benefits from a limited-slip Active M Differential on the rear for fully-variable torque distribution between the rear wheels, while an available M Traction Control system offers up to 10 different stages of electronic intervention.
There's also an electronically-controlled multi-plate clutch in the central transfer case for variable torque split between the axles, along with a redesigned double-joint spring strut front axle, new front suspension geometry, a new steering ratio, and a reworked engine oil supply system.
However, the addition of all-wheel drive traction will come at a cost – weight – with the powered front axle likely to add around 50kg to the mid-sizers' kerb weight, edging them closer to the 1800kg mark.
A set comprising 19-inch front and 20-inch rear alloy wheels are standard, wrapped in 275/35 front and 285/30 rear performance tyres – with Michelin track-focused tyres available as an option.
Exterior and interior styling features of the Competition xDrive siblings are identical to their rear-drive counterparts.
The 2021 BMW M3 and M4 Competition xDrive models will arrive in Australia in the fourth quarter of 2021. Local pricing and specifications will be announced closer to launch.
In the UK, the xDrive models command a £2260 premium over their rear-drive Competition siblings, equating to an increase of around 2.9 per cent – suggesting Australian prices could start at around $160,000 before on-road costs in M3 guise, or $165,000 in M4 form.