These heavy-duty clutch kits use aluminum lightweight flywheels with sport clutch components to give your clutch the grip and clamping force it needs to cope with high torque upgrades. Our kits were developed through racing programs by companies affiliated with our own race team - JB Racing, Sachs Sport, OS Giken, and UUC Motorwerks. JB Racing is the leader in aluminum lightweight flywheel upgrades. They are direct replacements for the stock dual-mass flywheels with steel contact surfaces and computer balanced to 14,000 RPM. JB has partnered with Sachs to spec sport/HD clutch discs and pressure plates that work seamlessly with their aluminum flywheels. The result is a clutch/flywheel upgrade package that functions a lot like the original clutch combo with near-stock levels of effort and engangement but with a much higher torque capacity. Don't let the clutch be your weak link in a highly tuned car!