Increasing the size or the surface area of a clutch increases the torque capacity of the system, however unlike brakes you’re generally not able to simply install a larger clutch. There are two methods that are used by performance clutch manufactures to increase the surface area;
Installing twin or triple plates in most cases can be done without modifying the bellhousing and can double or triple the torque capacity without having a detriment to the drivability. The Mantic Track series has a range of twin and triple plate kits which feature several different plate options to suit various applications from street to track.
This groove is a patented system that has been specifically designed to increase the Mean Effective Radius of the pressure plate and assist in heat removal. The increase in the Mean Effective Radius of the cover assembly gives a significant increase in torque capacity.
By adding the groove to the pressure plate, the inside radius of the friction face has effectively been increased. The first 5/16 inches(7.9375mm) of the pressure plate has all butbeen removed and added to this, there is progressively less material removed as the radius increases. The net effect of this is to move the effective inside radius further out.
The Mean Effective Radius of the clutch is directly proportional to the torque capacity of the system. Therefore as the Mean Effective
radius increases so does the Torque Capacity of the clutch. This system can be found in both the Mantic and 4Terrain performance clutch range.