Posted Dec 12th 2013 8:29AM
The Next Generation Of M Is Born
BMW has announced the 2015 M3 Sedan and M4 Coupe, high-performance versions of the new 3 Series and 4 Series that launched this year. The new Ms have stirred controversy in a variety of ways, but one must remember that the M cars traditionally don't follow a specific mould.
The new 3.0-litre inline-six makes 425 turbocharged horsepower from 5500 rpm all the way up to 7300 rpm.
Back in 1988, BMW launched the M3 with a high-revving four-cylinder engine even though the top non-M 3 Series model was equipped with an inline-six. The reason: the little four-banger weighed less. The power-dense 2.3-litre four produced 197 horsepower, which was enough to make the original M3 one of the most sought after performance BMWs of all time. Two successive generations of M3 stepped up the cylinder count to six and provided a nice bump in power, and the M3 that came after them was equipped with a screaming V8. The M3's history dictates that M cars aren't about staying the same - they're meant to push limits - and M Motorsport engineers decided that the new M3 Sedan and M4 Coupe would push limits best with a twin-turbocharged inline-six.
For those of you worried that the new mill will underwhelm, on paper it outperforms the last M3's 4.0-litre V8 in a number of areas, including weighing 10 kilograms (22 pounds) less. The new 3.0-litre inline-six makes 425 turbocharged horsepower from 5,500 rpm all the way up to 7,300 rpm – just 300 rpm before the redline is reached. That's five more horsepower than the V8, but more importantly, the 1800-rpm powerband is very broad. Torque from the turbo six is even more impressive: peak torque of 406 pound-feet starts at 1850 rpm and doesn't start falling off until 5,500 rpm, right when the engine starts to make peak horsepower. That compares very favourably to the V8's oft-bemoaned max torque of just 295 lb-ft.
Score one for the turbo M.