SCHWEINFURT – The new Škoda Fabia R5 is a winner: the brand’s latest rally model won the Czech Rally Championship in its debut season with Jan Kopecký/Pavel Dresler. In summer 2015, Škoda clinched a hat trick of WRC2 victories in the Polish, Finnish and German rounds of the World Rally Championship. The four-wheel drive model powered by a 1.6-litre turbocharged engine relies exclusively on ZF Race Engineering shock absorbers.
The powerful 280 hp, third generation Škoda Fabia complies with the R5 regulations issued by the Fédération Internationale de l’Automobile FIA. Consequently, it can also compete at national level as well as on the international stage – like in the WRC2 category of the FIA World Rally Championship WRC or the FIA Asia-Pacific Rally Championship.
The new rally model’s wheels are mounted on McPherson-strut suspension all-round. ZF supplies the dampers, which are subject to extremely high loads in this configuration. In addition to damping the oscillations resulting from suspension travel, the components also control the wheels in a McPherson type suspension. Therefore, the front dampers also fulfill steering and tracking tasks, while at the same time the damper is subject directly to longitudinal and lateral loads. When landing after a jump, the dampers are subject to extremely high loads in several directions. On top of this comes the rough environment found in rallying: the cars must survive scree and boulder sections gravel as well as rallies on fine gravel, mud, tarmac, and snow or ice. At the same time, the R5 regulations set significantly tighter budget constraints than for the less restrictive WRC regulations – the rules stipulate a large number of production components for the R5 models.
To fulfill every demand, ZF developed a special damper with external reservoirs. The damper’s machined reservoir tubes are manufactured from robust aluminium alloys. The dampers are three-way adjustable – two-way for low and high speed bump forces and one-way in rebound. The extreme forces, like those encountered over jumps, are controlled by hydraulic bump and rebound stops. In addition, the engineers can define different car ride-heights depending on the surface conditions. The Škoda Fabia R5’s ride-height is adjusted via a thread on the damper reservoir tube.
ZF offers a gravel suspension set for rallies held on unpaved roads. Dampers for the significantly rougher surface feature longer spring travel. They require a greater gas chamber, which is another reason why the external reservoirs are more generously dimensioned. All the damper curves provided by ZF can be set manually and are within the damper’s operating range.
During the development phase, Škoda and its development partner ZF subjected the damper to extreme loads to ensure the damper was ready-to-rally. Škoda subsequently homologated the Fabia R5 exclusively with ZF dampers. As a result, the rally drivers in the brand’s customer rallying programme also compete successfully with the German suspension technology.