The BMW Concept M4 GTS previews a more hardcore M4 Coupe, a high-performance special model honed for the track, yet being relatively fit for the road. Marking its global premiere at the Pebble Beach Concours d’Elegance weekend in California on 13 August 2015, the Concept M4 GTS also features an innovative water injection system and OLED (organic light-emitting diode) rear lights.
“While the BMW M4 Coupe embodies the ideal combination of motor sport genes and unrestricted everyday usability, the BMW Concept M4 GTS previews an emotionally powerful and exclusive special model conceived with an eye for trailblazing technology and a keen focus on the race track,” explains Frank van Meel, President BMW M Division. “Despite its outstanding track ability, it is still fully road-legal. This is racing technology for the road in the truest sense.”
For added precision and pace on track days, the BMW Concept M4 GTS features a manually adjustable front splitter and rear wing; both in exposed carbon , a lightweight CFRP (carbon-fibre-reinforced plastic) bonnet, and a wide front air intake.
The exterior paint shade is called Frozen Dark Grey Metallic, while the Acid Orange accent on the front splitter liven things up. The lightweight, forged and polished light-alloy wheels in 666 M styling also feature an Acid Orange accent. The 9.5 J x 19 (front) and 10.5 J x 20 (rear) wheels are fitted with Michelin Sport Cup 2 tyres (265/35 R19 at the front, 285/30 R20 at the rear).
Through the Concept M4 GTS, BMW also showcases its water injection system, and OLED illumination wizardry; which are “destined to make their series production debut in a new model to be unveiled at a later date”.
The turbocharged, six-cylinder engine powering the BMW Concept M4 GTS is equipped a water injection system; that is already employed in the BMW M4 MotoGP Safety Car, with added power and torque.
The water injection system, introduced by BMW M Division uses the physical effect of water when vaporising to draw the required energy from the ambient medium. The water is injected into the plenums of the intake manifold as a fine spray. When the water vaporises, the intake air cools significantly. As a result, the final compression temperature in the combustion chamber – and therefore the engine’s tendency to “knock” – is reduced, enabling the turbocharged engine to use higher boost pressure and earlier injection timing.
While an increase in output and torque is achieved, the system also reduced the thermal stress on performance-relevant components. Apart from the water injection system, the M4 GTS’s motor also gets a more effective cooling system. It comprises a main radiator plus additional radiators for the high- and low-temperature circuits, transmission and turbocharger in order to keep temperatures stable. The turbochargers are cooled by means of an indirect intercooler, assisted by an additional electric water pump.
Last but not the least, the BMW Concept M4 GTS is fitted with rear lights featuring OLED technology. OLEDs (organic light-emitting diodes) are a new type of light source producing full-surface and homogenous illumination – in contrast to LEDs, which emit light to a single point. Their low installation height of just 1.4 millimetres and the ability to actuate individual light modules separately create fresh design scope in lighting concepts. OLED technology also opens up new possibilities when it comes to a characteristic light signature for BMW models.