ACT ZX4-HDR4 Heavy Duty/Race Rigid 4 Pad Kit

The ACT ZX4-HDR4 kit is engineered for those who demand high performance from their clutch system. This kit features ACT's renowned Heavy Duty pressure plate, designed with an exclusive diaphragm configuration that enhances clamp load while minimizing deflection. This results in improved clutch longevity and reliability during intense driving conditions.

Construction and Materials

Each diaphragm undergoes a rigorous four-stage heat-treating process, ensuring exceptional durability and performance. The precision stamping of the pressure plate provides the necessary rigidity, which is critical for consistent operation. The 4-pad rigid race discs are constructed from high-quality ceramic friction materials, optimized for high heat tolerance and maximum performance. The chrome-moly hub is also heat-treated, enhancing its strength and durability.

Performance Characteristics

• Light to moderate pedal effort with aggressive engagement.
• Increased gear rattle is expected due to the rigid design.
• Moderate friction life, extended by ACT?s exclusive diaphragm design, though the rigid setup may lead to increased spline wear.
• Recommended strictly for race applications.
• Each unit is 100% clamp load tested and dynamically balanced for smooth operation at high RPMs.

Specifications

• Clutch Disc Diameter: 9.4 in (240 mm)
• Disc Material: Ceramic
• Input Spline Quantity: 23
• Input Shaft Diameter: 1 in
• Pressure Plate Type: Heavy Duty
• Torque Capacity: 574 ft/lbs
• Product Weight: 28.7 lbs
• Includes ACT Prolite flywheel and pressure plate bolts (M8-1.25 x 16mm).

Installation Notes

• For detailed installation instructions, click here.

Vehicle Fitment

This clutch kit is confirmed to fit the following vehicles:

• Mazda 3 (2004-2013)
• Mazda 6 (2003-2008)