The pack, available from July, boosts the output of the V8 engine powering the M5 and M6 by 15bhp to 567bhp; this makes them the most powerful production BMWs to date.
They are also noteworthy for recording the fastest ever official 0-62mph times for a BMW. Both the Competition Package-equipped M6 Coupé and Gran Coupé can complete the benchmark sprint in 4.1secs.
Emissions, consumption, torque and top speed remain unchanged, however - and straight-line performance gains are marginal. The Competition Package M5, for example, can hit 62mph in 4.2sec, just 0.1sec faster than the conventional version.
Opting for the package also adds sports suspension settings, sports steering, a sports exhaust with black chrome tailpipes and 20-inch lightweight alloy wheels.
BMW’s Active M Differential has also been further tweaked as part of the Competition Package, improving the car's cornering capabilities. In conjunction with the other adaptations the end result is improved traction and enhanced driving precision, says BMW.
The 'M Dynamic Mode' is also tuned, allowing higher thresholds before the stability control intervenes.
Aesthetically the Competition Package includes a new 20-inch M wheel design along with a sport exhaust system, featuring twin tailpipes finished in black chrome.
The Competition Package costs £6700 for M5 models, which start at £73,505. Specifying it on an M6 adds £6500 to the list price, which starts at £100,680 for the Coupé or £105,880 for the Convertible. It costs an additional £5,500 for Gran Coupé models, which start at £103,200.