BMW gave journalists a first technical briefing on the next-generation BMW 3 Series at its Miramas proving ground in France, outlining new chassis hardware for the base 320 and range-topping M350 xDrive, along with a new central driving dynamics software architecture.

BMW 320 Gets New Chassis and Larger Dimensions

The base BMW 320 rides on an all-new body with revised global stiffness targets, according to BMW. The front track width increases by 40mm and the rear track grows by 32mm compared with the outgoing model, while the wheelbase increases by 90mm.

Wheel diameter grows to 680mm. At the front, BMW retains a double-joint MacPherson strut layout but introduces revised kinematics for increased trail, slightly reduced camber and softer spring rates.

Conventional dampers are fitted with a Hydraulic Rebound Stop, a technology BMW says was carried over from the Neue Klasse iX3. Other front-axle changes include a stiffer axle carrier, a new shear panel connecting the shock tower to the firewall and revised anti-roll bar bushings.

The base car uses a fixed steering ratio and comes with 245/45R18 tires as standard.

At the rear, the new BMW 3 Series uses a five-link axle with Hydraulic Rebound Stop dampers, a stiffer camber arm, revised elastokinematics and increased stiffness at the top mount-to-body connection.

BMW says the stiffer connection is designed to reduce the delay between steering input and damper engagement during body roll. An Adaptive Suspension is available as an option across all variants, using electronically controlled dampers.

The optional system is always paired with Sport Steering and offers two driving modes: Personal and Sport.

BMW M350 xDrive Combines Inline-Six Power With Hybrid Technology

The range-topping M350 xDrive is powered by a 3.0-liter BMW TwinPower Turbo inline-six engine with 48V mild hybrid technology.

BMW’s provisional figures list a maximum output of 326 kW, equivalent to 443 PS in the EU and 437 hp in the U.S., along with 580 Nm, or 428 lb-ft, of torque. The company lists a 0-100 km/h time of 4.1 seconds and a top speed of 250 km/h, or 155 mph.

Standard equipment includes Adaptive M Suspension, Variable Sport Steering and a controlled rear differential lock.

The M350 xDrive offers three drive modes: Personal for everyday comfort, M Sport tuned for driving dynamics and M Sport+, which BMW describes as its maximum driving dynamics setting.

Chassis-specific hardware includes unique spring and damper tuning, front body struts, stiffer anti-roll bars and revised camber. Aerodynamic components include a front air deflector and a rear Gurney flap intended to improve high-speed stability.

A Driving Dynamics Brace connects the rear subframe to the car’s center structure. M Sport brakes use fixed calipers at the front axle and floating calipers at the rear.

Tire Options Range From 19 to 20 Inches

Tire sizes for the M350 xDrive range from 19 to 20 inches. The performance option is a Bridgestone Potenza Sport in 245/35R20 at the front and 275/30R20 at the rear.

A rolling-resistance-optimized Goodyear Eagle F1 Asymmetric 5 is also offered, measuring 245/35R20 at the front and 255/30R20 at the rear.

BMW confirmed that fuel economy figures will vary depending on tire selection but did not provide exact numbers.

M350 xDrive Uses Variable Torque Distribution

The M350’s xDrive system uses a multi-plate clutch that can fully decouple the front axle to reduce drivetrain losses or direct torque forward as driving conditions demand.

BMW says there is no fixed default torque split. In standard driving modes, the clutch is kept ready to close within approximately 100 milliseconds.

During DSC-off track driving, the system introduces additional clutch clearance to further reduce drag, increasing response time by roughly 20 additional milliseconds.

Torque distribution is calculated continuously by comparing driver input at the pedal and steering wheel against the rear axle’s available traction, using data from the 6D motion sensor.

BMW’s engineer said the system is not fixed at a 50/50 split and can send torque almost entirely to one axle in low-grip conditions, although the company does not publish a specific maximum front-axle torque figure.

Heart of Joy Software Becomes Central to Driving Dynamics

BMW calls its central driving dynamics architecture Heart of Joy. The system uses one central computer running a single software stack to coordinate all driving-dynamics functions.

BMW says this version is shared in principle with the software used in its electric Neue Klasse models but has been adapted for combustion and plug-in hybrid powertrains.

In electric models, BMW says the motor can react to driver input within milliseconds, allowing continuous torque shifting between axles to influence agility and stability directly.

Electric motors can also decelerate the car through recuperation at up to approximately 0.4g, which BMW says covers roughly 98 percent of everyday braking without engaging the friction brakes.

According to BMW, combustion engines cannot operate in the same way because torque delivery takes hundreds of milliseconds to build. In the 320 and M350, the central computer instead coordinates brake intervention, stability and traction control, the electronically controlled rear differential and steering through one software stack with no communication delay between separate control units.

BMW describes the hardware housing as identical to the electric-vehicle version, although it uses a different processor and software developed specifically for combustion powertrains. The company says this is the 10th generation of the software and that it was developed entirely in-house.

New 6D Motion Observer Monitors Vehicle Movement

New for this generation is the 6D Motion Observer, a sensor cluster that measures lateral, vertical and longitudinal acceleration along with roll, pitch and yaw.

BMW says the data gives the software a continuous and precise measurement of understeer or oversteer conditions independent of driver input, feeding directly into the dynamics controller’s decisions.

BMW described one example of the system during cornering. At a default torque split of roughly 40 percent front and 60 percent rear, a brake intervention on the inside front wheel assists turn-in, torque distribution shifts toward 30/70, and the electronically controlled rear differential lock engages only after the initial brake intervention begins to fade to avoid conflicting inputs.

BMW Adds New Efficient Dynamics Measures

BMW listed several efficiency-focused updates across the drivetrain and chassis, including a 48V mild hybrid system, active aerodynamic flaps, a lower-consumption 12V electrical system, tires and brakes engineered for reduced drag and wheel bearings with reduced friction.

An Efficient drive mode is said to increase range by up to 10 percent through powertrain adjustments and reduced comfort settings.

BMW said an Efficiency Coach feature providing live driving feedback is planned to arrive in the car and the MyBMW app after launch. The MyBMW app’s Trips section will also include efficiency statistics and gamification features.

What BMW Has Yet to Confirm

BMW did not release pricing, confirm final production names beyond “320” and “M350 xDrive,” or confirm the weight of the car.

The technical briefing provided an early look at the hardware and software planned for the next-generation BMW 3 Series, while additional details on its specifications, design and pricing have yet to be confirmed.