ACT ZM1-HDG4 Heavy Duty Race Sprung 4-Pad Clutch Kit for 1990-1993 Mazda Miata

Vehicle Fitment

• 1990-1993 Mazda Miata (Base/SE/LE, 1.6L I4 GAS FI, 5-Speed Manual)

Features

• Heavy Duty diaphragm pressure plate increases clamp load and durability
• 4-pad race-orientated sprung clutch disc for aggressive engagement
• Ceramic friction material with high heat tolerance for performance use
• Spring-center hub helps damp torsional vibration for smoother operation
• Light to moderate pedal effort with positive engagement feel
• Aggressive shifting with OE-to-mild gear rattle typical of performance sprung designs
• Precision balanced for smooth high-RPM reliability
• Recommended for high-horsepower street and occasional race applications

Specifications

• Clutch Disc Diameter: 7.9 in / 200 mm
• Disc Material: Ceramic friction
• Disc Type: Sprung 4-pad race hub
• Pressure Plate Type: Heavy Duty diaphragm
• Input Shaft Diameter: ~0.9375 in
• Spline Count: 22
• Approx. Torque Capacity: ~250 ft-lbs (~86 % over OEM)
• Product Weight: ~11.1 lbs
• Flywheel: Use with factory flywheel (not included)

Included Components

• 1x Heavy Duty diaphragm pressure plate
• 1x Sprung 4-pad race clutch disc
• 1x Clutch release bearing
• 1x Pilot bearing
• 1x Clutch alignment tool

Product Description

The ACT ZM1-HDG4 Heavy Duty Race Sprung 4-Pad Clutch Kit is a direct-fit high-performance clutch upgrade engineered for the **1990-1993 Mazda Miata** equipped with the 1.6 L engine and 5-speed manual transmission. Combining ACT's Heavy Duty diaphragm pressure plate with a 4-pad sprung race clutch disc, this kit delivers more aggressive engagement and increased clamp load compared to many OEM clutch assemblies, making it well suited for high-horsepower street builds and occasional race use. The ceramic friction material offers improved heat tolerance and durability under performance conditions, while the spring-center disc helps damp torsional vibration and maintain smoother engagement.

Designed for spirited driving, this heavy-duty clutch kit balances light to moderate pedal effort with confident engagement and quicker shifting response. While engagement is more aggressive than stock, it remains manageable for street use. Precision balancing and comprehensive clamp-load testing help ensure smooth operation at higher engine speeds. This kit must be used with the factory flywheel, which is **not included**, and is ideal for enthusiasts seeking a performance upgrade over the stock Miata clutch setup.