For as long as motorsports have existed, the quest for greater performance has been the focus.
And road vehicles are also frequently optimized. But with every increase in torque, the powertrain is also subjected to greater stress. Often a simple chip tuning is enough and the standard clutch is overloaded and starts to slip. What are the options for remedying this situation?
A very general distinction is made between two types of clutch upgrades: performance cl utches are clutches designed for performance-enhanced vehicles on the road. Here in particular, the problem often arises that when performance is increased, it is overlooked that the newly gained power must also be transferred. Series clutches are usually overtaxed because they are not designed for higher torques. A performance clutch corresponds in dimensions to the series components and can therefore be very easily exchanged for the series clutch. The difference lies in the use of much higher-quality friction linings (sintered or special organic lining) and a diaphragm spring on the pressure plate designed for the higher torque requirements. The allocation is vehicle-specific as a direct replacement for the series parts. Performance clutches are also frequently used in motorsports. On the one hand, of course, in the Gr. N, where only such solutions are allowed, but on the other hand also partly in other classes.
This is distinguished from pure motorsport clutches, which are not vehicle-specific clutches, but universal parts that are individually assembled for the respective area of application. It is possible to choose between different friction linings (sintered metal in various thicknesses, organic lining, carbon) and disc diameters. It is also important to match the number of driving plates to the area of application. Such motorsport clutches mean increased expense when first purchased, as the vehicle must be adapted to the clutch (flywheel, release mechanism, installation space, etc.), but they bring about significant advantages in terms of mass inertia and torque transmission. However, motorsport clutches are only suitable to a very limited extent for use in road traffic!
One of the biggest advantages that a motorsport clutch has over a performance clutch is the significantly lower mass moment of inertia. At first glance, you might think that the mass of a coupling (5-10 kg) is negligible compared to the mass of the vehicle to be accelerated (approx. 1,000 kg). However, what is often overlooked here is the gear ratio. If, for example, the clutch has a mass moment of inertia of 0.061 kgm², this acts at a ratio of 13.4:1 (1st gear transmission ratio) on the drive wheel with 180 times the amount (13.4²). If the mass moment of inertia is converted into vehicle mass, this results in an additional weight of around 145 kg in 1st gear, which has to be accelerated!
As a result, the following things should become conscious: through optimization measures in the crankshaft drive that reduce the mass moment of inertia, the acceleration behavior of the vehicle in the lower gears increases significantly. Conversely, the braking behavior also improves, of course, since less mass has to be slowed down. A wide variety of factors have to be taken into account for the correct design of a motorsport clutch: Torque, vehicle type (touring car or formula car?), area of application (standing or flying start?), installation space, clutch actuation, flywheel, regulations, budget, etc. – our team is always happy to provide sound advice!
