Tuning: BMW relies on KW suspensions
CUSTOMER SPORT Car manufacturers are relying on suspension and damper technologies from the KW Automotive Group for more and more customer sports projects. BMW, for example, equips the new M4 GT4 with solid piston dampers from KW.
In addition to the BMW customer sports models M4 GT4 and M240i Racing Cup, the M4 GT3 is also equipped with motorsport components from KW Automotive. Last weekend, the new GT4 racer competed as a pre-production M4 GT4 Concept race car at the 24 Hours of Portimão in Portugal and immediately took second place in the GTX class of Special GT Cars.
For production cars and racing cars
A close partnership has existed for years between the Bavarian carmaker and the Swabian suspension manufacturer. For example, KW Automotive manufactures BMW M performance components for selected production vehicles and also equips one or the other special model, such as the M3 CTR, the M3 GTS and the M4 GTS, with coilovers ex works.
M4 GT4 with motorsport dampers
A race car that complies with the GT4 regulations is fairly close to series production compared with race cars in the GT3 class. Depending on the balance-of-performance rating and the regulations, the turbocharged 3-liter inline six in the M4 GT4 produces up to 550 hp. Power is transmitted to the rear axle via a 7-speed automatic transmission, Drexler limited-slip differential and motorsport transmission software.
Nevertheless, one or two components, such as the rear wing concept or the carbon roof, are derived from the M4 GT3, BMW's big motorsport brother. BMW also attaches great importance to the new GT4 racer being maintenance-friendly for the teams and more cost-efficient than its predecessor.
Damping forces and characteristics
Fully in line with GT4 regulations, the M4 GT4 features dual power-adjustable KW Racing dampers. The displacement piston design (Solid Piston Technology) means that the working piston is no longer overflowed.
This alone allows much greater use to be made of hydraulics in the damper design than with other systems. Solid piston dampers generate completely different damping forces and characteristics than previous racing applications.
