2019 BMW 3 Series Gets More Horsepower, MagneRide-like Suspension
The Auto Start Stop function and the coasting function available in conjunction with the eight-speed Steptronic transmission in the new BMW 3 Series Sedan also use data supplied by the optional navigation system with data from the standard Active Guard driving assistance systems’ front camera. In this way, inefficient engine shutdown (for example when stopping briefly at junctions or roundabouts) can be prevented. Movement of vehicles ahead is registered in order to determine the ideal moment for the Auto Start Stop function to stop and start the engine.
The coasting function is now available when either ECO Pro or COMFORT mode is selected using the Driving Experience Control switch between nine and 99 miles per hour. The efficiency-enhancing decoupling of the powertrain only takes place in driving situations where performance and comfort are not compromised. If the driver suddenly lifts off the accelerator, the powertrain stays connected so that engine braking can be used to support deceleration. For the same reason, powertrain disconnection is also prevented when approaching a junction or a vehicle ahead.
BMW xDrive: fully variable and more efficient.
The latest version of the intelligent all-wheel-drive system splits drive torque between the front and rear wheels more efficiently than in the previous 3 Series model. The fully variable power transfer ensures maximum traction and directional stability in all road and weather conditions while also promoting sportier handling. This functionality comes courtesy of the electronically controlled multi-plate clutch in the transfer case which links up with the Dynamic Stability Control (DSC) system and constantly adjusts power transmission, precisely and in a fraction of a second, in response to the driving situation. In this way, any tendency of the vehicle to oversteer or understeer greatly reduced.
The system’s rear-biased set-up helps ensure the new BMW 3 Series Sedan retains the exhilarating driving experience drivers expect from a BMW. Sending more drive power to the rear wheels under normal driving increases agility when cornering. In situations which do not require all-wheel drive, the efficiency of BMW xDrive is increased by directing all the engine’s torque to the rear wheels. The weight of the system has also been reduced, while optimized oil supply increases internal efficiency.
Chassis Technology: Sportiness and comfort
When developing the body structure and chassis technology of the new BMW 3 Series Sedan, a number of clear priorities were used: enhanced driving dynamics, agile handling characteristics, high-precision steering and superior braking performance. The foundations for these attributes are provided by weight optimization, a low center of gravity, a perfect 50:50 front/rear weight distribution and, above all, by the increase in the front and rear track compared with the predecessor model, significantly increased camber values for the front wheels and the substantial increase in the stiffness of the body structure and suspension mountings.
Overall body rigidity is up 25 percent, rising to as much as a 50 percent improvement in certain areas. The increased rigidity of the body and suspension mountings enables the M Sport suspension and Adaptive M suspension to go about their work in the most efficient way possible allowing for suspension spring rates to be increased by 20 percent over the previous-generation BMW 3 Series Sedan without loss of comfort.
In addition to these measures, new shock absorber technology has been developed for the new BMW 3 Series Sedan. Used for the first time in a BMW model, the lift-related dampers are part of the car’s standard chassis and make a major contribution to the unique balance of sportiness and comfort, unrivaled by any other manufacturer, which defines the character of the new BMW 3 Series Sedan. The car’s handling and steering dynamics can be fine-tuned with a series of precisely matched chassis options. The functionally coordinated interplay of suspension, steering, tires, brake system and differential lock makes sport driving an effortlessly enjoyable experience.
Lightweight construction and increased rigidity deliver greater agility
The rigorous testing and development of the new chassis design enhances the agility of the new BMW 3 Series Sedan in a number of ways. Many details of the proven double-joint spring strut front suspension and five-link rear suspension have been upgraded. Along with the sportier handling, the car’s ride comfort and acoustics have both been improved. Aluminum swivel bearings and control arms for the front axle, aluminum wheel mounts and a new generation of wheel bearings for the rear axle significantly reduce unsprung mass.
The front axle, with its increased level of component rigidity, the shear panels used to connect the axle to the body and its specially tuned kinematics, enhances both steering precision and cornering dynamics. Factors contributing to the high level of comfort provided by the sedan include a hydraulically damped torque strut bearing, which eliminates vibration and oscillation. At the rear axle, extremely rigid control arms and axle sub-frames along with the use of thrust arms for the body mounting ensure very precise wheel location.
Body weight reduced by as much as 121 pounds, drag coefficient as low as 0.26.
As with the individual chassis components, the weight of the new BMW 3 Series Sedan’s body construction has been reduced. The progress achieved through BMW efficient lightweight measures is rooted in an intelligent material mix including increased use of high-strength steels and aluminum. The body-in-white is 44 pounds. lighter than the outgoing model and the front spring struts and engine sub-frame of the BMW 3 Series Sedan are now made of aluminum. This reduces the weight of the body structure by some 16.5 pounds. compared with the predecessor model. A further weight saving of almost 33 pounds. is achieved through the use of aluminum for the hood and front fenders.
The optimization of its aerodynamic characteristics benefits not only the efficiency of the new BMW 3 Series Sedan, but also its performance. The drag coefficient (Cd) of the BMW 3 Series sedan has been reduced to a low 0.26, a reduction of .03 Cd over the previous BMW 3 Series. Factors responsible for the new segment-leading figures include the almost completely sealed underbody, aerodynamically optimized wheels, the use of Air Curtains at the front of the car and the latest generation of active air flap control, which extends across the BMW kidney grille and lower air intake.
Premiere for lift-related dampers
A newly developed suspension and damping system contributes to the beautifully balanced handling of the new BMW 3 Series Sedan. The introduction of lift-related damper control reduces body movement perceptibly smoothing out vibrations caused by bumpy road surfaces and dynamic cornering, which paves the way for sporty, authoritative handling. The system adds extra hydraulic damping at the front axle and a compression limiting system at the rear. It is continuously variable and adjusts the damper firmness progressively according to the changing spring travel. This prevents excessive body dive when driving over large bumps and so avoids uncomfortable, nervous damping response.
At the front axle, the first line of defense against body vibrations is an additional element within the inner sleeve of the damper. Only when greater loads are encountered does the entire damper become active. The rear dampers adapt continuously to the driving situation. Even when the vehicle is carrying heavier loads, they provide the ideal degree of hydraulic damping for the situation at hand. Lift-related damping is an active element of the suspension set-up and is designed specifically to optimize the balance between sportiness and comfort. The positive effect of progressive suspension adjustment can also be felt in less demanding circumstances; even small bumps can trigger damper lift, which makes a noticeable difference in enhancing passenger comfort.
The new BMW 3 Series Sedan benefits from lift-related damping on both the standard and optional M Sport suspensions. With kinematics and elastokinematics clearly tuned for dynamic driving, the M Sport suspension features more rigid bearings and additional body struts, firmer springs and anti-roll bars, and an even higher degree of wheel camber.
During fast compression and rebound, the damping forces are some 20 percent greater than the values with the standard suspension. This means that the difference between the two suspension options is about twice as great as on the predecessor model. Another element of the M Sport suspension, which now also applies to the all-wheel-drive model variants of the new BMW 3 Series Sedan, is a 0.4 inch lower ride height.
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