BMW last week announced the new 2016 BMW M4 GTS giving BMW M GmbH a new and exclusive technological masterpiece that elevates the potential of the BMW M4 Coupe to an impressive new level. With its powerful, motor sport-inspired looks and high-performance technology, the BMW M4 GTS has its sights set squarely on the racetrack.
Thanks to an innovative water injection system helping boost power to 493 brake horsepower (500 horsepower) and track ready chassis, this Special Edition M vehicle recorded a lap time of 7 minutes and 28 seconds around the legendary Nürburgring-Nordschleife, the world’s most challenging race circuit, making a clear statement about this model’s exceptional dynamic abilities. At the same time, the sharpest BMW M4 of all can also hold its own on public roads. BMW M GmbH is launching the BMW M4 GTS in a special edition limited to 700 units worldwide, with 300 units of this high-performance Special Edition M4 available for the first time in the US market.
Performance boost through water injection
At the heart of each and every BMW M model is its engine. The BMW M4 GTS uses the multi-award-winning M TwinPower Turbo 6-cylinder in-line engine from the BMW M4, capable of 7,600 revolutions per minute but adds innovative water injection technology to give the 3.0-liter unit a substantial power boost. Unusually high-revving for a turbocharged engine, it offers linear power delivery over a wide engine speed range. An innovative water injection system, used for the first time in a road car, takes this 6-cylinder in-line turbocharged unit to new performance heights by relaxing the thermal constraints on power and torque. The system has already proved itself on racetracks around the world on board the BMW M4 MotoGP Safety Car, this year’s lead safety car in the world’s top motorcycle racing series.
The engine develops its maximum power of 493 bhp – an increase of 16 percent over the BMW M4 – at 6,250 revolutions per minute. Peak torque has been increased by 10 percent to 442 pound-feet, and is maintained over a very wide rev band (4,000 rpm to 5,500 rpm). It accelerates from a standstill to 60 miles per hour (96 kilometers per hour) in a mere 3.7 seconds, on the way to a governed top speed of 189.5 mph (303.2 kph). Despite the significant extra power, the engine also excels on fuel efficiency, providing similar levels to those found in the BMW M4 Coupe.
Innovative water injection system
The BMW M4 GTS is the first production road car to be fitted with a trailblazing water injection system. With this arrangement, the BMW M engineers have utilized the principle that water absorbs heat from the surrounding air when it changes phases. Water is injected as a fine spray into the intake manifold plenum chamber where it evaporates (phase change), significantly lowering the temperature of the intake air. This action reduces the final compression temperature in the combustion chamber, minimizes the risk of knock and allows the turbocharged engine to operate with higher boost pressure and advanced spark timing. The result is increased power and torque, and a substantial improvement in efficiency. Despite the extra power output, thermal stress on all performance-related components is reduced. All of these features ultimately help to diminish wear and prolong engine life.
Increased power, reduced full-throttle fuel consumption
The benefits of water injection can be utilized in various ways, depending on engine and vehicle type. In particular, the engineers have considerable latitude when deciding how to balance their priorities between increased power and fuel efficiency. If water injection is taken into account in the design of a high-performance engine right from the start, it is possible to use turbochargers with a higher boost ratio and compression ratio. At the same time, power losses from an increase in ambient temperature (> 68° F) can be compensated by increasing the amount of water injected.
Additional engine highlights
The BMW M4 GTS turbocharged engine features a very rigid closed-deck crankcase design that makes it possible to develop higher pressure in the cylinder for improved power output. Instead of liners, the cylinder bores feature a twin-wire arc-sprayed coating, which results in a significant reduction in engine weight.
On the track, the high performance capability of the BMW M4 GTS places extra demands on the engine oil supply system. In designing this system, the BMW M division has once again taken full advantage of its extensive motor sport experience. The aluminum oil sump is designed to limit the movement of the oil under the influence of strong lateral forces, while an oil suction pump and a sophisticated oil return system to the turbocharger help to maintain stable oil circulation under extreme acceleration and deceleration. Oil is supplied continuously to all engine components in all driving situations, whether in everyday driving or during a hard weekend drive at the track.
The typical BMW M exhaust system design features four tailpipes, in this case each with an 80-millimeter diameter and laser-engraved M emblem. The expected performance car engine exhaust note is provided by a carefully designed lightweight titanium rear silencer.
M TwinPower Turbo technology
The BMW M4 GTS engine’s M TwinPower Turbo package comprises two fast-responding mono-scroll turbochargers, High Precision Injection, VALVETRONIC variable valve lift control and Double-VANOS continuously variable camshaft timing. The result is smooth and efficient power delivery with extremely sharp response.
7-speed M double-clutch transmission with Drivelogic
The BMW M Division’s 7-speed M double-clutch transmission with Drivelogic (M DCT) sets standards in terms of smooth power delivery, lightning quick up-shift gear changes, perfect rev-matching downshifts and track-ready design. In addition to automatic shifting, this highly advanced transmission also enables shifting without torque interruption, using the steering wheel shift paddles or center console mounted gear lever. Manual mode also offers a specially configured launch control system that provides ultra-fast acceleration off the line, with optimal gear changes for the subsequent upshifts.
Aluminum and Carbon-Fiber construction
First and foremost, an ultra-dynamic driving experience depends on a suspension system that combines low weight with high stiffness. Just like the BMW M4, the BMW M4 GTS is equipped with lightweight aluminum control arms, wheel carriers and axle subframes. On the double-joint spring-strut front axle alone, this cuts weight by more than 10 pounds compared with conventional steel components. Play-free ball joints and specially developed elastomer bearings provide optimal, direct transmission of longitudinal and transverse forces. The aluminum stiffening plate, carbon fiber–reinforced thermoplastic (CFRP) front strut tower brace and additional bolted connections between the axle subframe and body structure all make for a stiffer front end.
Precise engineering also extend to the steering system
The steering system has also been adapted to the BMW M4 GTS’s track capabilities. The steering torque curve, always critical for a smooth steering feel, has been further optimized by modifications to the front suspension kinematics and the incorporation of features such as asymmetric steering support mounts and a motor sport-derived, custom-designed, milled swivel bearing. This design allows optimized axle geometry for lateral dynamics and steering torque, which again translates to enhanced driving dynamics.