Originally offered in 1986 as a homologation special to allow BMW's entry into the German Touring Car Championship, the M3's popularity and steadily increasing sales for each iteration motivated the company to continue developing this unique combination of driving dynamics, comfort and luxury in a compact machine and offer a new version each time the underlying 3 Series was reborn. Americans were first introduced to the M3 sports sedan concept in 1988.
The all-new 2008 BMW M3 Sedan will arrive in March 2008, features the first V8 in a series-production BMW M3 (along with its coupe and convertible counterparts) and cost $54,575. It will also feature driver-adjustable settings for crucial dynamic controls including steering, damping and stability (and an available steering-wheel-mounted "MDrive" button to store the preferences), and a sporting interior that can be optimized to a driver's desires including the comprehensive entertainment/navigation system operated through BMW's latest iDrive controller.
The move to eight cylinders in the fourth generation BMW M3 provides a powerplant offering the seemingly disparate characteristics of more power, increased efficiency and reduced weight when compared with the previous six-cylinder M3 engine. Displacing 3,999 cubic centimeters (4.0 liters), the new light-alloy engine produces 414 hp at 8,300 rpm and 295 pound-feet of torque at 3,900 rpm with 85 percent of the maximum torque available consistently through 6,500 rpm. This power output represents a 24% increase over the six-cylinder from the last generation M3 and it comes with a 7% weight saving. Compression ratio is dialed in to 12.0:1 and redline is set at 8,400 rpm.
The V8 engine of the new BMW M3 Sedan boasts the company's variable double-VANOS camshaft management. Offering extremely fast and responsive valve timing, this technology reduces charge cycle losses and improves the output, torque and response of the engine, with a positive influence on fuel economy and emission management.
A volume flow-controlled, pendulum-slide cell pump supplies the engine with lubricating oil, delivering the quantity required by the engine. Wet sump oil lubrication, optimized for dynamic performance, ensures consistent oil supply to the high-rpm engine at all times, particularly in extreme braking maneuvers. The system features two oil sumps—a small oil sump in front of the front axle subframe and a large oil sump behind it.
A new, comprehensive electronic management system coordinates all engine functions with optimum efficiency and maximizes operational integration with the clutch, gearbox, steering and brakes. In addition, the engine control unit performs a wide range of on-board diagnosis functions and masterminds the ancillary engine units.
And the increased performance with better economy comes from the lightweight engine. At 445 pounds, it is 7% or 33 pounds lighter than the previous model's Inline-6. Lightweight components do not stop with the alloy engine block. The crankcase is made of a special aluminum-silicon alloy eliminating the need for cylinder liners. Despite the need to resist high combustion pressures and engine speeds—this is the "fastest" production engine ever produced by BMW as it can reach 8,400 rpm—the engineers managed to keep the compact and rigid crankshaft weight down to 44 pounds.
Power from the BMW M3 Sedan's V8 is transmitted to the rear wheels through a close-ratio six-speed manual gearbox. The performance parameters of the M3 dictated heat management as a key design factor for both the transmission and clutch. The transmission features integrated temperature-dependent oil cooling management, while internal ventilation maximizes heat dissipation for the twin-disc clutch.
The new final drive comes with a Variable M Differential Lock generating up to 100% locking action with fully variable action whenever required, ensuring optimum traction on all road surfaces.
In addition to the traditional 6-speed manual transmission, the new M3 will be available with a unique 7-speed double clutch gearbox specially designed for a high-rpm engine. The M double-clutch transmission with Drivelogic (M DCT Drivelogic) shifts gears without the slightest interruption in the flow of power. As a result, M DCT Drivelogic is able to extract the most performance possible from the car while also providing a smooth comfortable shift from one gear to the next.
The process of shifting gears is basically the same as on BMW's proven Sequential M Gearbox, meaning that even when shifting gears manually there is no need for a clutch paddle and the driver may keep the gas pedal on the floor during the shift process.
The Drivelogic control offers 11 different shift programs to suit the needs of individual drivers. Drivelogic offers 5 programs that allow for automatic operation of the transmission as well as 6 manual programs. Manual operation can be performed via a new sports shift lever exclusive to the BMW M3 or via paddles on the steering wheel (pulling the right-hand paddle to shift up, the left paddle to shift down).
In its gearshift characteristics, the new M double-clutch transmission with Drivelogic is ideally matched to the fast-revving V8 engine in the new BMW M3. M DCT Drivelogic will make its debut initially on the upcoming 2008 M3 Convertible and will be available as an option on the BMW M3 Sedan (and Coupe) soon afterwards.
Providing sure-footed responsive handling for a high-performance, powerful and luxurious sedan, while keeping mass under control, presented numerous challenges for the BMW M3's engineers. The result are new, aluminum chassis components developed specifically for this model. The design begins with placing components in such a way as to create a 50/50 front/rear weight balance.
Virtually all of the front-end components are aluminum, including the front struts, swivel bearings, central subframe and an additional thrust panel below the engine serving to maximize lateral stiffness of the entire front section.
From the rear axle subframe through the transverse arms and track arms, to the wheel mounts re-configured in their kinematics and stiffness, to the mounting points for the longitudinal arms and the aluminum dampers, virtually every detail on the five-arm rear axle is made of aluminum and is new for this model. These weight-reduction measures and materials help reduce weight by approximately 5.5 pounds when compared to the previous BMW M3.
Both the front and rear axles feature hollow anti-roll bars optimized for their function and weight. Incorporating two additional longitudinal reinforcement bars, axle kinematics are perfectly tailored to the overall character of the car. The result, in terms of both stability and weight, conforms to the balanced performance concept of the BMW M3 Sedan.
A suitably powerful braking system for a car with this much performance was specifically developed for the new M3. The internally-vented, cross-drilled cast iron discs measure 14.2 inches in diameter at the front and 13.8 inches in the rear. Featuring large compound disc brakes and electronic anti-lock, stopping power for the new BMW M3 is strong, precise and consistent. They are connected to a floating aluminum hub by cast-in stainless-steel pins. This configuration reduces the thermal loads on the discs, thus increasing their performance and service life. An electrically-driven pump provides the system's vacuum power.
Service - and safety - is enhanced thanks to an integrated wear indicator which, through a dash display, allows the driver to monitor the condition of the brake linings. Brake service can thus be administered when necessary without guesswork.
Standard M-style light-alloy spoked wheels measure 18 x 8.5 inches with 245/40 low-profile tires at the front and 18 x 9.5 with 265/40 tires at the rear, can be supplemented by optional 19-inch versions in comparable widths and design.
Rear-wheel drive keeps the rack-and-pinion steering of the BMW M3 Sedan free of drive forces. A further enhancement is hydraulic Servotronic power assistance controlling steering forces as a function of road speed. There is also a choice of two different control maps activated through normal and sport modes with a console-mounted button.
In Sport mode the BMW M3 provides direct and immediate response with a relatively high steering effort. In the Normal mode, power assistance is comfort-oriented and requires less steering effort.
The electronic Dynamic Stability Control (DSC) monitors driving conditions and intervenes through the application of brakes and reduced engine power to stabilize the BMW M3 and help avoid major over- or under-steer situations.
In addition to engine controls and the ABS, other systems integrated in the DSC are Automatic Stability Control (ASC), which prevents the wheels from spinning on surfaces with reduced traction; the Start-Off Assistant, which prevents the car from rolling back when setting off on a grade, as well as Cornering Brake Control (CBC), which prevents the car from spinning or swerving out of control when applying the brakes in a bend.
The latest version of DSC includes additional functions for even greater driving safety. Whenever the driver is likely to apply the brakes in full within the next few seconds, the system builds up pressure in the hydraulic brake circuit and pre-loads the brake pads to ensure an immediate response. The Brake Drying feature removes water film from the discs in wet conditions, thus reducing the chance of water interfering with the initial braking process.
The optional Electronic Damper Control (EDC) allows the driver to tailor the vehicle's chassis dynamics to his or her preference through one of three modes: Sport, Normal and Comfort.
The response of all dynamic driving systems is carefully tailored to the power and performance of the new BMW M3, with electronic intervention of the various systems naturally taking the dynamics of the car into account. Indeed, the driver even has the option to individually configure specific parameters, thus adjusting the response of the car to his personal preferences.
Front to back, the design of the new BMW M3 Sedan evokes a purposeful, sporting message. The front end, though clearly a BMW based on the double-kidney shaped grill, flat headlight units with standard Xenon headlamps, boasts three large air intakes below the grill. Since the structure and configuration is determined to primarily feed air into the engine compartment, the BMW M3 Sedan, like BMW M cars in general, intentionally forgoes fog lamps featured on 3 Series models.
The "face" of the new BMW M3 also includes a power dome in the middle of the aluminum hood which, though longer than that of the 3 Series Sedan, blends harmoniously with the overall design.
The two front side panels boast a special sign of distinction characteristic of a BMW M Car and referred to by the designers as "gills," which incorporate the tri-color (blue/purple/red M3) logo. Rear-view mirrors developed for the new BMW M3 fulfill an important aerodynamic function helping reduce air resistance. Further down the side-line, the pronounced side-sills, give the BMW M3 a light and sporting look.
The four metallic paints reserved for BMW M cars (Melbourne Red, Jerez Black, Interlagos Blue and Silverstone) highlight the body, contours and proportions of the four-door with particular intensity. In addition to these unique hues, the BMW M3 is available in Alpine White, Jet Black, or Sparkling Graphite Metallic.
The interior of the BMW M3 has always been a place designed for performance driving, but without compromising the comfort of the driver and the passengers. The new BMW M3 Sedan continues this tradition with the latest innovations. The five seats are surrounded by powerful contours and flowing lines highlighting in particular the concave and convex surfaces. The horizontal lines dominating the area around the dashboard as well as the harmonious surfaces of the side linings give the interior a dynamic note.
The cockpit control area tapers out between the front seats into a newly designed center console which discreetly "swings" towards the driver. Finished in black leather, the console harmoniously continues the instrument surrounds and the control area in terms of both color and shape, comprising three function switches (Power, DSC, and optional EDC) for activating and deactivating the electronic driving programs on the side facing the driver.
There is no question as to the heritage of the vehicle upon opening the door of the new BMW M3 thanks to the M car logo in the door sills. The unique nature of the vehicle carries to the dash where the dual circular instruments typical of BMW - the speedometer and fuel gauge as well as the tachometer and oil temperature display - are in specific M style. A feature typical of BMW M cars is the variable warning zone on the tachometer that informs the driver of the recommended engine speed depending on the engine oil temperature. The borderline between the yellow pre-warning zone and the red warning zone moves up as a function of increasing oil temperature to the maximum limit of 8,400 rpm. The digital displays presenting the time, the outside temperature and odometer, as well as the various warning lights, are positioned between the two circular instruments.
As an option, both the front seats are available with backrest-width adjustment, while the rear seats may be equipped with folding seatbacks which provides the 15.9 cubic foot luggage compartment even greater capacity.
A premium AM/FM/single-disc CD audio system comes standard with an auxiliary input jack. Individual entertainment options include SIRIUS satellite radio, HD radio and a USB-enabled port for control of an Apple iPod or iPhone media player. These three options can be bundled together in the Technology Package, should one choose to have them all together.
For vehicles equipped with Navigation, the comprehensive information and entertainment systems are controlled by the refined BMW iDrive. Selecting the Navigation/iDrive option also brings the performance-oriented, steering-wheel-spoke-mounted Mdrive button.
Occupant safety begins with the design of the new BMW M3's body structure. Together with defined deformation zones, the use of high-strength steel ensures smooth and direct transmission of forces in a collision and optimum absorption of loads acting on the car. The space available for deformation is also used to avoid any damage to the passenger cell and keep damage to the body itself to a minimum, even in a severe collision.
The electronic restraint systems are tailored to the ultra-strong structure of the body. Six airbags as well as the belt latch tensioners and belt force limiters are activated by the car's central safety electronics as a function of the type and severity of a collision. Sensors located in the center of the car within the B-pillars and in the doors "tell" the safety electronics which component will offer the occupants optimum protection, with the "proper" restraint systems being activated in the event of a collision.
The driver and front passenger are protected by frontal and side airbags housed in the seat backrests. These four airbags are activated in two stages, depending on the severity of the impact. Through its size alone, the curtain head airbag protects the car's occupants on both the front and the outer rear seats. And the risk of leg injury in a head-on collision, finally, is reduced on the driver's side by defined deformation of the footrest.
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