..:: M3Addict.com :: e46 BMW M3 ::..

December 1, 2000:

FOR IMMEDIATE RELEASE:
Robert D. Mitchell
Product Communications Manager
201-307-3790 / rob.mitchell@bmwna.com
David J. Buchko
Product Communications Specialist
201-307-3789 / dave.buchko@bmwna.com

THE NEW BMW M3
A LEGEND IS REBORN

Woodcliff Lake, New Jerrsey, December 1, 2000. For enthusiasts of ultimate automotive performance, it’s a magic name: BMW M3. Combining the all-around excellence of the BMW 3 Series with the spectacular performance and handling prowess of BMW M, the M3 is the formidable BMW sports car that has won – again and again – the accolades and comparison-test victories of the world’s motoring critics while providing its buyers with real practicality. Now, there is a new M3 – an all-new generation of this legendary sports car that surpasses even its acclaimed predecessor. Entering production in February 2001, the new 3rd-generation M3 has been derived from the successful E46 3 Series coupe. It is powered by a new, dramatically more powerful BMW M 6-cylinder engine; equipped with new and unique stability enhancements; designed and equipped to radiate BMW M sportiness and quality as no car at its price level has ever done. At a base price of $46,045, the new M3 brings together BMW M virtues in a brand-new way that is bound to set off another round of applause from those who appreciate the very best in road capabilities.

A BRIEF HISTORY OF THE M3

The 1st-generation M3 was essentially a racing car tamed for road use. Offered in the U.S. from 1988 through 1991, it was based on the then-3 Series generation (internal platform designation E30) and was a winged, spoilered 2-door sedan powered by a rip-snortin’ BMW M 4-cylinder engine of 2.3 liters and 192 hp. This was a full-on BMW M engine, with 4 valves per cylinder at a time when no regular-production BMW had more than 2; an individual throttle for each cylinder; honed cylinders; and other racing-style engineering finery. Over time, there were hotter versions, both road- and race-going; just a single model was sold in the U.S. That M3 certainly wasn’t for everyone; but it was a hearty and competent sporting machine, and even today it has a devoted following.

The 2nd-generation M3 is better known. Based on the then-current E36 3 Series and making its debut as a 1995 model, this M3 had a mission beyond the usual BMW M dedication to great performance and handling: to bring BMW M and its wonderful driving machines to a wider spectrum of buyers in the U.S. This was accomplished by powering the M3 not with a traditional, highly elaborate BMW M engine, but rather with a specially developed version of what was now standard BMW practice: an inline 6-cylinder engine with dual overhead camshafts, 4 valves per cylinder and a single throttle. Taking this approach, BMW M created an engine of 3.0 liters (vs. the standard 325i models’ 2.5) and a solid 240 horsepower. The strategy was perfect: Within the range of speeds American drivers experienced, this engine provided thrilling performance, yet cost thousands less to produce. The rest of the car was very much the same M3 that Europeans could buy. In 1996 the engine grew to 3.2 liters and delivered more torque. In either form, the e36 M3 was loved by America’s enthusiasts and critics alike. “Anyone who has audited a class in German Engineering Appreciation is familiar with the simple equation: 3.2 liters to the M power equals heart-pounding thrills,” opined Motor Trend in September ’97. “The BMW M3 has it all,” reported Car and Driver in December ’94. “Scintillating speed, brilliant handling, a utilitarian package.” This 2nd-generation M3 was offered through 1999; a convertible and a 4-door sedan joined the original coupe model along the way, extending M3 virtues to buyers with differing priorities.

THE NEW M3:E46 PERFECTION, M MUSCLE

As universally acclaimed as the 1995-99 E36 M3 was, progress never stops at BMW – nor at BMW M. With the debut of the new E46 3 Series generation for the ’99 model year, it was inevitable that an E46 M3 would someday appear. Now it is here. At any point in time, the diligent people who conceive, design and engineer BMW vehicles are always striving toward the future, toward something even better than that already achieved. So it is with the 3 Series, a core BMW product. Car and Driver, naming the new 3 Series to its 10Best list in February ’99, put it this way: “…the car is now in its fourth generation, each iteration better than the one before it. Every time BMW polishes the design, it brings the 3 Series a bit closer to perfection.” Thus the M3, too, could be brought closer to perfection. As before, the first model of the new M3 generation is a coupe. It is based on the E46 3 Series coupe, introduced only a year ago in 323Ci and 328Ci form and already evolved into the further improved 2001 325Ci and 330Ci. YYet the new M3 is more than just a “3 Series plus”: Like all M Cars, it is very much its own machine, a true and dazzlingly gifted sports car.

A NEW APPROACH TO POWER CREATES NEW CAPABILITIES

As multi-talented as any M Car is, its heart is always the engine. The new M3’s heart is utterly new, and a dramatic departure from the already wonderful engine of its predecessor. After the resounding success of that special, simpler, less costly engine, BMW M has decided to endow all new M3s with the same engine: a “world engine,” and one that does indeed embody the more exotic, costlier, even higher-performance concept formerly reserved for other markets. Why? Because M owners and enthusiasts demand and expect more; the bar must be raised. The previous engine’s dual overhead camshafts, 4 valves per cylinder, single throttle, “rev range” to a then-impressive 6800 rpm – such features and characteristics have become normal for high performing regular-production automobiles. To further the M3’s leading-edge position, it was time to move on to an even higher-caliber machine. Under the new M3’s domed aluminum hood, then, is an engine like none other – even more spectacular than the one that powered 2nd generation European M3s.

AN ALL-NEW BMW M ENGINE:THE S54, WITH NEARLY 100 HP MORE

In its broad concept, the new M3 engine, designated the S54 1, shares the familiar layout of other BMW inline 6-cylinder engines. Virtually all of its engineering details, however, are unique and oriented to the very highest level of performance. Given that other current BMW “sixes” have an aluminum block with cast-iron cylinder liners, it may be surprising that the new M3 engine (like its predecessor) has a cast-iron block. Why? Compacttness is the primary reason. An inline six is longer than a V-6, and BMW nurtures the inline layout because of its superior smoothness and sound. An aluminum block’s cylinder liners take up space; with liners it would not have been possible to achieve the engine’s 3.2-liter displacement without lengthening the block. The second reason is sttrrengtth. Given that this engine develops fully 333 hp from 3.2 liters – significantly over 100 hp per liter – its internal stresses are immense. According to M3 Project Director Siegfried Friedmann, BMW engineers researched a silicon-impregnated aluminum block (as used in BMW V-8 and V-12 engines), which would not require liners. But they became convinced that a cast-iron block could best sustain the engine’s high cylinder pressures and very high piston speed at maximum rpm. (Current Formula 1 engines attain piston speeds around 25 meters per second; with 24 m/sec. at its rpm limit of 8000 rpm, the S54 is very close.) The block accommodates the engine’s new bore and stroke of 87 x 91 mm; these have increased from the previous U.S. engine’s 86.4 x 89.6 mm to give a displacement of 3246 cc, up from 3152. Increased displacement, however, is not the major contributor to the huge power increase over the previous M3 engine. Playing much larger roles in the nearly 100-hp increase are the new engine’s induction, combustion and exhaust engineering, together with its execution as a hiigh--rrpm engiine. And the starring role here is played by a brand-new cylinder head that could be termed “exotic.”

TOUR DE FORCE:THE CYLIINDER HEAD

To achieve more than 100 hp/liter, an engine needs exceptional breathing ability. The new engine’s head is not merely new relative to the previous U.S. M3; it is also new relative to the previous European engine, which delivered 317 hp (SAE net). Feature-by-feature, the new head (of aluminum as before) differs sweepingly from the previous U.S. head, becoming more like other BMW M cylinder heads. Features shared with the BMW M5’s V-8 engine, for example, are noted with an asterisk (*): Doublle VANOS steplessly variable valve timing**.. The previous U.S. engine had VANOS 2 variable valve timing on its intake valves only: a 2-stage system, with one timing setting for low, one for high engine speeds. The new engine has stepless Double VANOS, which varies valve timing on the intake and exhaust camshafts without the “step” of the 2-stage system. Though this VANOS is employed in current 3 and 5 Series 6-cylinder engines, as used in the M3 engine it varies timing over a wider range and contributes in a major way to the engine’s stratospheric power output. Intake timing is varied by 60o, exhaust by 46 o, vs. 40 o /25 o 3. As in all BMW engines where it is employed, VANOS is hydraulically actuated in response to electronic controls.
VANOS prresure pump. The VANOS system has its own radial-piston hydraulic pump; in regular-production BMW engines the main oil pump supplies the pressure to operate VANOS. This pump is included in the exhaust camshaft’s VANOS mechanism, and produces up to 120 bar (1740 lb./sq in.) of pressure. Herbert Vögele, who directs engine development at BMW M, explains that this high oil pressure enables the M3’s VANOS to vary valve timing more quickly at very high rpm than would the regular-production hydraulic system. Thus BMW M refers to the M3’s VANOS system as High--Presure Double VANOS. Unique valve mechanism.. All current BMW double-overhead-camshaft (DOHC) engines employ “bucket-type” hydraulic lifters, actuating the valves directly with minimum noise and no periodic adjustment. For the S54’s rpm potential, BMW M needed a valvetrain with less reciprocating mass. To achieve this, they created a different actuating mechanism, using finger-type rocker arms. Pivoting on their own shafts (one on the intake side, one on the exhaust), these small – one could almost say dainty – arms reach out to provide the actuating surface between camshaft and valve. As the entire arm does not move the distance of valve lift, its effective reciprocating mass is less than its actual mass – and it weighs less than the “bucket tappets” in the first place. When all is said and done, the effective mass is 30% less; in turn, this allows lighter valve springs, which also reduce inertia. The lower valvetrain inertia helps the engine attain its 8000-rpm capability. As the system involves no hydraulic maintenance of valve clearance, it does have to be inspected periodically. Lead engine engineer Helmut Himmel asserts that it is unlikely that clearance will actually require adjustment, but if so it is done with shims (tiny metal discs of various thickness) without removal of the camshafts.

The rocker-arm arrangement also results in less friction. Unlike the rocker arms of BMW’s V-12 engine, however, these do not incorporate rollers, which would add too much mass for such a high-revving engine. Where the regular-production 6-cylinder engines have a simplex (single) primary chain driving the exhaust camshaft and a smaller secondary chain driving the intake camshaft from there, the S54 has a full duplex (double) chain driving both camshafts directly. As usual with BMW engines, the chain is hydraulically tensioned and needs no periodic adjustment or replacement. Extra-high comprression ratio. At 11.5:1, the M3 engine has the highest ratio in current BMW production. (M5: 11.0:1, also quite high.) Machined surfaces. “Engineering finery”: The combustion chambers and intake ports are completely machined, for smoothness that facilitates airflow. The exhaust ports are partially machined. For durability, the valve seats are of especially hard steel. A 3-layer stainless-steel head gasket ensures effective sealing of the head to the block. Head casting and sealing. Extreme strength in the cylinder head has been achieved by making it a single aluminum casting. This construction, though more difficult to realize than the previous European engine’s 2-piece head casting, also saves weight – a very significant 29 lb. As this weight savings is at the top of the engine, it helps lower the car’s center of gravity.

INDUCTION SYSTEM:BMW M TRADITIION, STATE-OF-THE-ART TECHNOLOGY

The new M3 returns to a BMW M tradition: an individual throttle for each cylinder. Positioned much nearer the cylinders than a single throttle can be, these bring atmospheric pressure practically right to the cylinder. The “lag time” inherent in airflow into the cylinders is thus greatly reduced and the engine can react more quickly to throttle movements.In principle, the M3 system – electronically controlled individual throttles – is like that of the M5 even though no actual components are shared. All six throttles operate from a single shaft, each in its own throttle body right at the intake ports. Via the accelerator pedal and its two potentiometers, the driver gives the commands, which in turn are processed by the engine control module and received by a DC servo motor. The motor drives the throttle shaft through a tiny gearbox. Upstream of (and acoustically decoupled from) the throttle bodies are the six intake trumpets, made of weight-efficient fiberglass-reinforced PA6 thermoplastic; their diameter-to-length ratio was calibrated with a computer program of BMW’s Formula 1 racing department. In turn, the trumpets are laser-welded into the induction plenum of the same composite material to form a single assembly.

As on the M5, M Driving Dynamics Control provides Normal and Sport settings for throttle response. In the Sport setting, selected via a console switch, the ratio of throttle opening to pedal movement is increased so that apparent engine response is even quicker. Remarkably, even the transitional response of the electronic engine controls (primarily ignition timing) is altered to suit. Drivers will find one or the other setting more to their liking, or choose them according to driving conditions; the system always reverts to Normal when the engine is started.Together with the stepless VANOS, this elaborate induction system contributes to the engine’s immense breathing and fuel/air processing capabilities.

For the complete 2001 BMW M3 Press Release: Click Here.