The BMW M4 offers drivers a spectrum of driving experiences through its selectable engine modes: EFFICIENT, SPORT, and SPORT PLUS. Each mode is meticulously engineered to alter the engine’s behavior and overall vehicle dynamics, catering to different driving preferences and conditions. Understanding the nuances of these modes is key to unlocking the full potential of your BMW M4.
In SPORT and SPORT PLUS modes, the engine control unit prioritizes responsiveness and immediate power delivery. A significant aspect of this is the management of the turbocharger wastegates. Unlike in EFFICIENT mode, where wastegates might open earlier under partial load, in SPORT and SPORT PLUS, they remain closed. This strategic closure ensures that exhaust mass flow is consistently directed through the turbines, keeping the turbochargers spinning at a higher base speed, even when the driver is not demanding full power. This pre-spooling of the turbos, combined with specific engine control functions designed to accelerate turbocharger activation, results in a noticeably sharper throttle response. The car reacts more keenly to even subtle accelerator pedal inputs, providing a more engaging and dynamic driving experience.
Another critical element differentiating these modes lies in how the BMW M4’s drivetrain manages torque build-up. Typically, engineers must consider the limitations of the drivetrain when calibrating engine torque delivery. Engines can often generate torque far quicker than a conventional drivetrain can smoothly handle. This mismatch can lead to drivetrain oscillations, similar to a torsion spring being stretched and then vibrating, manifesting as unwanted juddering. To mitigate this, many vehicles employ engine control strategies that dampen the rate of torque increase, ensuring a harmonious and comfortable driving experience. However, the BMW M4, designed for high performance, features a remarkably rigid drivetrain. Components like a carbon fiber driveshaft, a rear axle directly bolted to the body, and robust drive shafts are engineered to cope with rapid torque build-up, much like a racing car. This rigid drivetrain is fundamental to the M4’s spontaneous and immediate response, especially in SPORT and SPORT PLUS modes.
EFFICIENT mode, in contrast to the more aggressive SPORT settings, prioritizes comfort and fuel efficiency. In this mode, the engine’s response is deliberately smoothed out, with a greater emphasis on relaxed driving. Conversely, SPORT PLUS mode throws comfort considerations entirely out the window. It represents the most unfiltered and direct connection between driver input and vehicle reaction. In SPORT PLUS, all electronic filtering functions are minimized or deactivated, making the engine respond instantly and intensely to accelerator pedal movements. This mode demands a skilled driver who can manage the M4’s raw power and responsiveness. SPORT PLUS mode maximizes the engineering capabilities of the engine, transmission, chassis, and control systems to achieve the fastest possible performance, particularly suited for track driving or highly spirited road driving, where every millisecond counts.
