Racing provided the reason for the original BMW M3's 1986 creation as the company had to produce road-going homologation versions of its BMW 3-Series Coupe to enter the motorsports version in the German Touring Car Championship. Popularity, proven by strong sales demands, provided the impetus to continue developing the M3, making it both a better performer and more inviting road car as it evolved along with the underlying 3 Series, the company's most popular, upon which it is based.
In 1988 North Americans received their first taste of the high-rpm, naturally aspirated 2.3-liter four-cylinder BMW M3 Coupe 192-hp and thus was born a legend on this side of the Atlantic. The next generation arrived in 1995 with a 3.0-liter (and later, 3.2-liter) 240-hp inline-six powerplant. In 1997 the first BMW M3 Sedan joined the family and the first BMW M3 Convertible followed shortly thereafter. The most-recent version, available from 2001-2006 as either a coupe or convertible, again was offered with six-cylinder power, this time providing 333 hp from its 3.2 liters. This vehicle was BMW's first use of SMG (Sequential Manual Gearbox) for the U.S. market.
BMW M3 Coupe US-Version
The all-new 2008 BMW M3 Coupe and BMW M3 Sedan features the first V8 in a series-production BMW M3, and cost $57,275 and $54,575 respectively. It also features driver-adjustable settings for crucial dynamic controls encompassing engine response, steering, damping and stability (with an available steering-wheel-mounted "MDrive" button to store the preferences), and a sporting interior that can be optimized to the driver's desires including the comprehensive entertainment/navigation system operated through BMW's latest iDrive controller.
Lightweight, efficient V8 at the heart of the BMW M3
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 Coupe 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 separate throttle butterfly for each cylinder - eight in this instance - is a feature adapted from BMW M's racing heritage and provides immediate reaction to the gas pedal at all times. Two stepper motors operate the four throttle butterflies on each row of cylinders, giving the engine a particularly sensitive response at low speeds together with an immediate reaction whenever the driver presses down the accelerator for extra power and performance.
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.
A highlight of the engine management system is the use of ion-current technology to determine engine knock as well as misfire and poor combustion events within the cylinders. In contrast to conventional methods, this monitoring and control function is performed precisely where the phenomena occurs—within the combustion chambers. The spark plug in each cylinder senses and controls the risk of knocking, at the same time monitoring the correct ignition and recognizing any misfiring. In other words, the spark plug acts as an actuator for the ignition and as a sensor monitoring the combustion process, and is therefore able to distinguish between a misfire and poor combustion. This dual function of the spark plugs facilitates the diagnostic procedures required in service and maintenance.
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.
Manual transmission, twin-disc clutch and Variable M Differential Lock
Power from the BMW M3 Coupe'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 percent locking action with fully variable action whenever required, ensuring optimum traction on all road surfaces. Responding to differences in speed between the right and left rear wheel, the Variable M Differential Lock also offers ideal support further enhancing the positive features and characteristics of rear-wheel drive.
Optional M double-clutch transmission with Drivelogic
In addition to the traditional 6-speed manual transmission, the new M3 is 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 which made its debut on the 2008 M3 Convertible and is available as an option on the BMW M3 Coupe (and Sedan) soon afterwards.
Engineering a chassis which is "faster than the engine"
Providing sure-footed responsive handling for a high-performance, powerful and luxurious coupe, while keeping mass under control, presented numerous challenges for the BMW M3's engineers. The result is a new, aluminum chassis 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 Coupe.
Compound brake system
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.
Servotronic steering with two manually adjustable control maps
Rear-wheel drive keeps the rack-and-pinion steering of the BMW M3 Coupe 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.
Latest-generation of Dynamic Stability Control
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.
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