BMW has already tantalised the adrenal glands of M-fanatics around the world by pulling the covers off its M4 Coupe Concept in August and now the company has spilled the beans on the mechanical workings of the production model.
In keeping with BMW's latest naming strategy, the M3 Coupé will effectively be replaced by the M4, while the M3 badge will continue to live on the boot lid of the hottest four-door 3 Series, which will be technologically identical to the M4.
A sore point for many M fans is that the previous M3's normally aspirated, high-revving V8 is being replaced by a more efficient force-fed six-cylinder motor in the new models. Yet the propaganda machine claims that BMW has combined the virtues of the previous engine with the strengths of turbo technology.
Furthermore, BMW is confident that the thousands of laps performed on the Nürburgring Nordschleife have prepared the models for the transition.
WILL IT REV?
For starters, the new straight-six is not exactly low-revving. While it won't reach the sonorous 8300rpm power peak of the V8, BMW promises that the new unit will at least spin beyond the 7500rpm mark. Plus points of the new turbo configuration, of course, are improved efficiency (by up to 25 percent) and a more linear power delivery over a wider rev range.
According to BMW, the new motor will churn out approximately 320kW and more than 500Nm (up from 309kW and 400Nm), so you can expect it to royally smash its predecessor's 4.6-second 0-100km/h time - particularly since the car's overall weight has been reduced by around 80kg to tip the scales at less than 1500kg.
NUTS AND BOLTS
Delving into its inner workings, the direct injection six-cylinder engine features a closed-deck crankcase design that enhances rigidity and allows extreme cylinder pressures to be withstood. You'd want that, given the immense boost provided by the two mono-scroll turbochargers.
Yet will the sound of the motor still induce goose flesh? Here BMW hints that aural delight is still provided in abundance by an “innovative flap arrangement” in the twin-pipe exhaust system.
Purists will also appreciate the fact that the M4 and M3 will still come with a manual gearbox as standard and the six-speed unit even blips the throttle on downshifts. A seven-speed M Double Clutch Transmission with DriveLogic and Launch Control will be optional.
To keep the models as agile as a verbally-cornered politician, M3 and M4 are underpinned by upgraded axles at both ends, the design improvements resulting in lower weight and improved rigidity. At the front end you'll find a double-joint spring strut design, while a five-link set-up does service at the back.
The Active M Differential has been further improved through the use of an electronic actuator that constantly varies the locking effect as required, to offer better traction and less understeer when exiting corners.
Owners will still have the option of switching the DSC stability nanny off completely, but those seeking a more liberal safety net that still allows wheel slip and drifting can dial in the M Dynamic Mode.
Varying suspension stiffness is also possible for those that tick the Adaptive M suspension option box, which offers Comfort, Sport and track-biased Sport+ damper settings.
However, you won't have to pay more to pander to your steering-assistance whims, as the newly developed electromechanical steering system offers the aforementioned three modes.
Finally, to bring the Monsters to a halt in a hurry, lightweight BMW M compound brakes are fitted as standard, promising outstanding stopping power and high resistance to fade. BMW M carbon ceramic brakes can be had for an additional outlay.
Tempted? The new M4 and M3 are set to go on sale during the second half of 2014.