Sports Car Newsletter

More Info
Car News & Articles on Cars
BMW M5: Muscles from Munich

BMW M5: Muscles from Munich

Source: BMW | Published: June 23, 2004

BMW M GmbH takes super sports sedan motive power into a new dimension with the unveiling of its high-revving ultra-powerful V10 engine destined for the E60 M5.

The engine shares more than just its number of cylinders with the Formula 1 engine that powers the BMW WilliamsF1 team. Technology forged in the heat of motorsport has enhanced the processes and components used in this new powerhouse engine.

As you would expect from BMW M, this high-performance normally aspirated engine generates enormous pulling force over its entire speed range.

The BMW M V10 is the only high-revving power unit to be featured in a series-production car. The M5's V10 boasts a cubic capacity of 5.0-litres and produces a maximum output of 507 bhp (378 kW) and a maximum torque of 384 lb-ft, making the M5 the most powerful production model in the BMW line-up.

It has been 20 years since BMW introduced the concept of the ultra-high performance sedan with the arrival of the original E28 M5. At that time the straight-six engine set the benchmark for naturally aspirated performance power units, and every successive M5 has continued this tradition.

M drivers thrive on accelerative thrust and driving dynamics. Engine torque and the transmission ratio significantly influence the drive forces at the driven wheels and the high-revving V10 allows an optimum transmission ratio, thus guaranteeing impressive forward thrust.

The compact, high-revving normally aspirated engine boasts a red line of 8,250 rpm. Compared to the previous M5 V8 engine, performance has increased by a massive 25 per cent. In keeping with its racing bloodline, the M5 surpasses the magical 100 bhp per litre output, its specific output being on par with that of racing cars.

BMW, one of the leaders in engine construction, has made a name for itself primarily as a manufacturer of inline engines. But its V-engines are also something extremely special.

The two five-cylinder banks of the V10 are arranged at an angle of 90-degrees to achieve a mass balance of the crankshaft drive, optimized for low vibration and increased comfort.

To ensure maximum stiffness and resist the high loads resulting from combustion pressure, engine speed and vibrations, a bedplate design has been chosen for the crankcase.

For an optimum alignment of the crankshaft, grey-cast iron inserts have been integrated into the aluminum bedplate, which also serve to enhance acoustics, increase vibrational comfort and ensure a high oil supply rate.

The extremely stiff crankshaft is supported by six bearings. In the new M5, it is the first time that BMW has used a bedplate design for a production V-engine.

The one-piece aluminum cylinder heads of the V10 engine are arranged in banks. The V10 power unit features four valves per cylinder, a typical BMW trait. All valve train components are of low mass. Thus, for example, the M engines feature for the first time low-weight, flow-optimized 5 mm-shaft valves, spherical valve tappets with hydraulic valve play compensation and single valve springs. All this results in a considerable mass reduction, which is a prerequisite for the realization of the high-revving concept.

The bi-VANOS variable valve timing featured in the new M5 engine ensures an optimum charge cycle, thus helping to achieve extremely short adjustment times. This means in practice: increased performance, an improved torque curve, optimum responsiveness, lower consumption and fewer emissions. Thanks to the bi-VANOS technology, intake and outlet valves are always opened and closed at precisely the right moment. The naturally aspirated engine uses ten flow-optimized intake trumpets to “inhale” air from two intake plenums. Each cylinder has its own throttle, a feature typical of racing cars. All throttles are actuated simultaneously and are electronically controlled in order to make the engine highly responsive in the lower speed range, as well as to achieve an immediate response of the vehicle at the high end of the performance spectrum. The exhaust system of the new M5 engine is made of seamless stainless steel and has a dual-flow design all the way to the silencers. The exhaust gases leave the system through four tailpipes, now a regular M trademark. The exhaust system complies with the European EU4 and the US LEV2 emission standards. The MS S65 engine management system is the central factor behind the V10's outstanding performance and emission data. With more than 1,000 individual components, this engine management system is unparalleled in its package density. Its processors are the most powerful currently approved for use in automobiles, as high engine speeds and comprehensive management and control tasks demand the utmost from this system.

Receiving more than 50 input signals, this system calculates for each individual cylinder and for each individual cycle the optimum ignition point, the ideal cylinder fill, the injection quantity and the injection point. At the same time this system calculates and makes the necessary adjustments for the optimum camshaft angle and the optimum position of the ten individual throttles.

The ionic current technology featured by the engine management unit is a technological highlight which serves to detect engine knock, misfiring and combustion misses.

Utilizing the spark plug in each cylinder, this system helps to pinpoint engine knock, to check for correct ignition and to detect any ignition misses. Thus the spark plug has a dual function - as an actuator for the ignition and as a sensor for monitoring the combustion process.

Ionic current measuring is done directly during the combustion process. The ionic current satellite receives signals from the five spark plugs of each cylinder bank. Dependent on the load, it amplifies these signals and transmits them to the engine management system for analysis, which, for example, perfectly adjusts the ignition point of each cylinder via knock control to the combustion process. All this results in benefits for the driver of the new M5 - lower fuel consumption, higher torque and enhanced performance.

Pricing and further specification details of the new BMW M5 will be announced closer to launch.

2007 BMW M5
Back to Car News

Sports Car Forums - The Forum for Sports Car Enthusiasts

Latest topics: