ACT BM17-HDR4 Heavy Duty Race Rigid Clutch Kit - 4-Pad

The ACT BM17-HDR4 is a Heavy Duty Race Rigid 4-Pad Clutch Kit engineered for race use. It pairs ACT's most popular Heavy Duty pressure plate with a ceramic 4-pad rigid race disc, delivering aggressive engagement, fast shifts, and the high heat tolerance required for track applications. Note: This is a conversion kit — an ACT flywheel is required and is not included.

Heavy Duty Pressure Plate:

• Exclusive diaphragm design increases clamp load, reduces deflection, and maximizes clutch life
• All diaphragms undergo a four-stage heat-treating process for consistent, reliable performance
• Precision cover stampings provide rigidity and dimensional consistency
• 100% clamp load tested for verified performance before leaving the factory
• Computer spin balanced to within 0.25 oz-in for smooth, high-RPM reliability

4-Pad Rigid Race Disc:

• High-quality ceramic friction materials for excellent high-heat tolerance and maximum grip
• Chrome-moly hub is heat-treated for strength and long-term durability
• Lightweight rigid construction enables quicker, cleaner gear changes
• 4-pad design is well-suited for smaller disc sizes used in smaller displacement engines
• Aggressive engagement character — faster shifts with harsher engagement compared to street discs

Performance Characteristics:

• Light to moderate pedal effort with aggressive engagement feel
• Moderate friction life, extended by ACT's exclusive diaphragm design
• Rigid disc design may increase spline wear over time — expected for race applications
• Increased gear rattle is normal with this disc type
• Recommended for race use only — not intended for street driving