The new BMW 4 Series Coupe presents a series of technical measures with the focus on optimizing driving dynamics, now boasting a completely reengineered chassis. BMW’s latest G22 4 Series was developed to provide a captivating level of dynamics. During the pre-drives, many have associated the chassis underpinning the new 4 Series Coupe with the main attributes of a surgical scalpel: precise and sharp.
The new premium, mid-class coupe from Bavaria combines the unique exterior design with the tried-and-tested chassis of the 3 Series, which has undergone major, precision tweaks to raise driving dynamics and sheer sportiness to a whole new level.
Increased Rigidity All-Around
The new generation of the 4 Series Coupe sports an increased body rigidity, a lower center of gravity, added torsional rigidity and stiffening parts and a tweaked chassis geometry, mounting and overall set-up.
Thanks to the individualized exterior styling, orbiting around the new kidney grille design, and the extensively modified chassis and suspension technology, the 2021 BMW 4 Series Coupe is now, more than ever in the past, clearly and sharply differentiated from the 3 Series.
As part of the innovations undergone by the chassis, the new 4 Series Coupe boasts a completely sealed underbody, which further helps improve aerodynamics.
Together with the enhanced air flap control, it was possible to reduce the aerodynamic drag coefficient up to Cd = 0.25 for the new 420d Coupe version.
Furthermore, the track width of the rear axle on the new 4 Series Coupe is increased by 23 millimeters compared to the 3 Series Sedan. Along with the increased negative front wheel camber, the lateral stability is dramatically improved when taking corners at high speed.
The new BMW 4 Series Coupe also boasts a perfect 50:50 weight distribution between the 2 axles and a millimeter lower center of gravity compared to the G20 3 Series.
The dampers with special, lift-related characteristics are included in the standard chassis technology of the new 4 Series Coupe.
For those clients looking to obtain maximum driving dynamics or to find a balance between sportiness and comfort, the new 4 Series Coupe can also be specced with the optional M Sport suspension, the Adaptive M Suspension with variable sport steering, the M Sport brake system and M Sport rear-axle differential.
Damping is performed by means of active, lift-related components which can ensure the optimal balance between sportiness and comfort. Even on the new 4 Series Coupe equipped with the standard chassis, the ground clearance is 10 millimeters lower (8 millimeter in case BMW xDrive is installed) than on the 3 Series Sedan.
The distinct dynamics and handling characteristics, as well as the increased damping forces, are further sharpened up thanks to the fitted anti-roll bars and firmer springs.
On the high-end M440i xDrive and M440d xDrive version, the optional M Sport suspension employs state-of-the-art kinematic and elastokinematic components for the lift-related dampers, which ensures a stiffer setting for the suspension and enhanced dynamic handling.
Other cutting-edge solutions applied to the M Sport suspension include additional body struts, more rigid mounts, firmer anti-roll bars and a higher degree of negative wheel camber.
The Adaptive M Suspension: The high-end choice for supreme dynamics
On the new 4 Series Coupe, BMW introduces the optional Adaptive M Suspension, which combines the virtues of the M Sport suspension with electronically-controlled dampers as to obtain an optimal agility level and body stability.
The use of electronics and sensors permits a fine tuning for the suspension. With the help of continuously adjustable valves, it is possible to measure the damping force individually on each wheel, also taking into account the vehicle load.
By going into the Driving Experience Control menu, the suspension settings can be easily adjusted to cater to the driver’s needs. As already known, there is a wealth of driving modes that can be chosen from, such as ADAPTIVE, SPORT or COMFORT, and there also exists the possibility to configure the chassis in an INDIVIDUAL mode.
The ADAPTIVE mode is made to adjust itself to the very driving style of the driver. Multiple systems and components are working in cooperation to variably and actively adjust the chassis settings.
The steering, damping and accelerator responses are coordinated with the 8-speed Steptronic transmission, as to ensure a higher level of dynamics or improve traveling comfort. The car can also use map data from the Navigation system to further prepare the chassis ahead of a bend or junction.
High-tech steering technology
The new BMW 4 Series Coupe is standardly equipped with the Electronic Power Steering system and the Servotronic speed-adjusting power assistance. There’s also the optional choice of the Variable Sport Steering, which is an integral part of the M Sport suspension and Adaptive M Suspension.
The Variable Sport Steering actively adjusts its behaviur in relation to changes in the steering angle as to provide a sharp, direct and precise response. Thus, the maneuvering and cornering capabilities of the new 4 Series Coupe are radically improved, while reducing the physical force and the number of steering wheel turns.
Wide range of alloy wheels available
17-inch light alloy wheels are standard on the new 4 Series Coupe. In addition, the M Sport trim models and the M440i/M440d xDrive variants also come with standard 18″ light-alloy M design wheels.
The new M Sport Pro version features standard M light-alloy wheels in 19-inch format. There’s also the choice of several mixed-size tires and rim designs, in 18-inch and 19-inch dimensions, as well as high performance tires.
If this is not enough, the new 4 Series Coupe can also be optionally specced with the special, 20″ light alloy wheels available as part of the BMW Original Accessories program.
High-performance M Sport brake system offered in the new 4 Series Coupe
The M Sport brake system is available for the new 4 Series Coupe with a distinguishable trait: blue or now also red-painted calipers with the ///M logo sported on their outer surface.
What sets the M Sport brake system apart is the innovative lightweight construction, consisting of cast iron friction rings combined with an aluminum brake disc chamber. This technology ensures an excellent braking performance as well as a reduced weight.
On the range-topping M440i xDrive/M440d xDrive, the M Sport brake system comes as standard, while for the rest of the powering versions, it is offered as optional equipment.
The M Sport brake system is also designed to ensure an optimal thermal resistance. In the cockpit, the high-performance braking system is clearly noticeable by the distinct pressure points on the pedal and the short pedal travel.
Furthermore, the M Sport brake system also employs a four-piston fixed configuration for the front wheel calipers and single-piston floating configuration for the rear wheel calipers.
The M Sport brakes work in complete harmony with a host of stabilizer systems and solutions such as the DSC, DTC, ABS and the newly integrated Start Off Assistant.
The Performance Control featured as standard on the new 4 Series Coupe further optimizes the vehicle’s directional stability during high braking phases, specifically when the two rear-axle wheels are running on surfaces with different coefficients of friction.
This is done with the help of a slight corrective impulse sent via the steering wheel, as to return the car to the normal straight path.
The M Sport brake system is also enhanced to support the functioning of the electromechanical parking brake system, which is integrated into the technology of the rear-wheel calipers and is complemented by the DSC.
M Sport differential for added stability and cornering dynamics
The rear-axle, electronically controlled M Sport differential with fully variable locking function is standard equipment on the high-end M440i xDrive Coupe and M440d xDrive Coupe models.
It can also be optionally configured on the 430i Coupe and 430d xDrive Coupe, if the M Sport suspension or the advanced Adaptive M Suspension are also specified.
The M Sport differential works on the basis of precise limitation of the rotational speed equalization effect for the rear-axle wheels. The electronically controlled differential is also working in close cooperation with the DSC (Dynamics Stability Control) system to reduce the natural tendency to understeer in cases of rapid cornering, for example.
The M Sport diff channels the additional engine power that cannot be transferred to the wheel on the inner side of the curve (the one susceptible to lose grip the most) towards the exterior wheel, rather than applying the brakes to neutralize the skid effect.
Thus, the new 4 Series Coupe attacks all curves and road bends with a state-of-the-art precision and poise, which guarantees a superior level of dynamism and all-rounding safety. This, in term, also helps to accelerate out of corners in a sharp and fast manner.
Thanks to the electronic management of the drive power distribution between the two rear wheels, the new 4 Series Coupe achieves a particularly remarkable level of stability when undertaking a series of consecutive, quick bends or changing lanes at the same time as braking.
The M Sport differential is also designed to improve traction in situations when the two rear-axle wheels are positioned onto surfaces with different friction characteristics.