ACT ZM4-HDSS Heavy Duty Performance Street Sprung Clutch Kit for Mazda MX-5 Miata

ZM4-HDSS kit features ACT's most popular Heavy Duty pressure plate and most popular street disc. ACT Heavy Duty pressure plates use exclusive diaphragm design to increase clamp load, reduce deflection and maximize clutch life. All diaphragms endure a four-stage, heat-treating process for unparalleled performance. ACT pressure plates have precision cover stampings to provide rigidity and consistency. ACT's Performance Street discs feature premium organic materials with high copper content for better heat transfer and steel-backed lining for greater burst strength and durability. These discs have reduced marcel for faster shift action to complement ACT pressure plates, with increased strength and reliability. HD/Perf Street Sprung Light to moderate pedal effort, smooth positive engagement, OE to mild gear rattle; Longer friction life, extended by ACT's exclusive diaphragm design; Carefully engineered, precisely assembled, accurately balanced, with premium organic friction materials for heat tolerance and reduced fade; Recommended for street and race use; 100% clamp load tested and dynamically computer balanced for smooth high RPM reliability

• "Excellence in Performance", backed by the best one-year warranty in the industry!

The ACT ZM4-HDSS Heavy Duty Performance Street Sprung Clutch Kit combines ACT’s Heavy Duty pressure plate with a Performance Street sprung disc for dependable street and race performance. Designed for drivers seeking stronger clutch engagement without excessive pedal effort, this kit delivers smooth, positive operation with improved durability compared with many original-equipment clutch systems.

The ACT Heavy Duty pressure plate uses an exclusive diaphragm design to increase clamp load, reduce deflection, and help maximize clutch life. Its diaphragm is processed through a four-stage heat-treating procedure for consistent performance, while precision cover stampings improve rigidity and dimensional stability. The included Performance Street disc uses premium organic friction material with high copper content to improve heat transfer and resistance to fade. Steel-backed lining adds burst strength and durability, while reduced marcel supports faster shift action and a responsive pedal feel.

Each ACT ZM4-HDSS kit is carefully engineered, precisely assembled, accurately balanced, 100% clamp-load tested, and dynamically computer balanced for smooth high-RPM reliability. It is recommended for street and race applications requiring longer friction life, moderate pedal effort, and reliable engagement. This kit is listed for select Mazda MX-5 Miata applications from 2007 through 2012; verify the vehicle’s year, transmission, engine configuration, and original clutch specifications before ordering. ACT backs its performance clutch products with a one-year warranty.

Product Specifications & Technical Data

• Brand: ACT
• Part Number: ZM4-HDSS
• Product Type: Automotive clutch kit
• Pressure Plate Type: Heavy Duty diaphragm pressure plate
• Disc Type: Performance Street sprung disc
• Friction Material: Premium organic material with high copper content
• Intended Use: Street and race applications
• Balancing and Testing: Dynamically computer balanced and 100% clamp-load tested

What’s Included

• ACT Heavy Duty pressure plate
• ACT Performance Street sprung clutch disc

Fitment: Select 2007–2012 Mazda MX-5 Miata applications, including the model years provided. Confirm detailed vehicle fitment before installation.

Features:

• Heavy Duty diaphragm design increases clamp load, reduces deflection, and helps extend clutch life.
• Four-stage heat-treated diaphragm provides consistent performance and long-term durability.
• Premium organic friction material with high copper content improves heat transfer and resistance to fade.
• Reduced marcel and steel-backed lining support faster shifts, smooth engagement, and increased disc strength.

Fitments:
2006 Mazda MX-5 Miata Grand Touring
2006 Mazda MX-5 Miata Sport
2007 Mazda MX-5 Miata Grand Touring
2007 Mazda MX-5 Miata Touring
2008 Mazda MX-5 Miata Grand Touring
2008 Mazda MX-5 Miata Touring
2009 Mazda MX-5 Miata Grand Touring
2009 Mazda MX-5 Miata Touring
2010 Mazda MX-5 Miata Grand Touring
2010 Mazda MX-5 Miata Touring
2011 Mazda MX-5 Miata Grand Touring
2011 Mazda MX-5 Miata Special Edition
2011 Mazda MX-5 Miata Touring
2012 Mazda MX-5 Miata Grand Touring
2012 Mazda MX-5 Miata Special Edition
2012 Mazda MX-5 Miata Touring
2013 Mazda MX-5 Miata Club
2013 Mazda MX-5 Miata Grand Touring
2014 Mazda MX-5 Miata Club
2014 Mazda MX-5 Miata Grand Touring
2015 Mazda MX-5 Miata 25th Anniversary Edition
2015 Mazda MX-5 Miata Club
2015 Mazda MX-5 Miata Grand Touring

Air Freight Prohibited: false
Not Carb Approved: false
Ltl Freight Required: false
Prop 65: Y
Part Type: automotive
Epa: N/A
Carb Acknowledgement Required: false
Regular Stock: t
Units Per Sku: 1