ZM1-HDR4 - ACT Heavy Duty Race Rigid 4 Pad Clutch Kit
Note: Must be used with factory flywheel.
Specifications
| Item Description | ACT Heavy Duty Race Rigid 4 Pad Clutch Kit |
|---|---|
| Product Weight (lbs.) | 10.3 |
| Torque Capacity (ft/lbs.) | 250 |
| Torque Capacity Over OE | 86% |
| Disc Material | Ceramic |
| Clutch Disc Diameter (Inches) | 7.9 |
| Clutch Disc Diameter (Millimeters) | 200 |
| Input Shaft Diameter (inches) | 0.9375 |
| Pressure Plate Type | Heavy Duty |
| Warranty | 12 Months (view details) |
Description
ZM1-HDR4 kit features ACT's most popular Heavy Duty pressure plate. 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 4-pad rigid race discs are made with high quality, ceramic friction materials. The chrome-moly hub is heat-treated for strength and durability. The lightweight, rigid design allows for quicker shifts and smooth, trouble-free service. With the 4-pad rigid race disc, engagement is harsher, but shifting is faster. The 4-pad rigid race disc is well-suited for the smaller disc sizes in smaller engines.
| Feel | Light to moderate pedal effort, aggressive engagement, increased gear rattle |
|---|---|
| Life | Moderate friction life, extended by ACT's exclusive diaphragm design, rigid design may increase spline wear |
| Quality | Carefully engineered, precisely assembled, accurately balanced, uses select ceramic friction materials for high heat tolerance and maximum performance |
| Recommended Use | Recommended for race use only |
| ACT Difference | 100% clamp load tested and dynamically computer balanced for smooth high RPM reliability |
Vehicle Fitment
| Application | Engine |
|---|---|
| 1990 Mazda Miata Base | 1.6 L4 GAS FI 1597cc | DOHC |
| 1991 Mazda Miata Base | 1.6 L4 GAS FI 1597cc | DOHC |
| 1991 Mazda Miata SE | 1.6 L4 GAS FI 1597cc | DOHC |
| 1992 Mazda Miata Base | 1.6 L4 GAS FI 1597cc | DOHC |
| 1993 Mazda Miata Base | 1.6 L4 GAS FI 1597cc | DOHC |
| 1993 Mazda Miata LE | 1.6 L4 GAS FI 1597cc | DOHC |
Kit Contents:
Frequently Asked Questions
- Are ACT clutches balanced?
- Yes! All ACT clutch assemblies are computer spin balanced to within .25 oz-in to guarantee help smooth operation across the entire RPM range. For comparison, stock production clutches are typically balanced to within .50 oz-in. Lower is definitely better!
- Will an ACT clutch increase pedal effort?
- ACT pressure plates are specifically designed to handle high torque applications. With ACT's durable design, expect an increase in pedal effort between 15-40% (Heavy Duty) and 50-80% (Xtreme), depending on the application. Clutches developed with less pedal effort often result in a lack of longevity, torque capacity and/or engagement quality.
- Do ACT clutches require a break in period?
- For organic street discs, we recommend breaking in the clutch for 300-500 miles with mild engagement, such as stop-and-go city driving prior to racing or spirited driving. ACT race discs usually only require a few hard slips to lap in the surfaces prior to normal driving or racing. Do not overheat the clutch during the break in period, as this can result in friction surfaces fusing together, hot spots, and friction surface glazing.
- Are ACT clutches repairable or rebuildable?
- In some situations, rebuilds or repairs may be possible (see warranty), after inspection of the clutch assembly. Please contact our technical department for further information. Because of special modifications, we do not recommend servicing by a general clutch rebuilder.
- How much does an ACT clutch weigh?
- The weight of the ACT clutch assembly will usually be the same as a stock OEM clutch assembly.
PROP 65 WARNING
This product can expose you to chemicals including carbon black, glass wool fibers, and silica (in clutch discs), chromium and nickel, which are known to the State of California to cause cancer or birth defects or other reproductive harm. for more information, visit www.P65Warnings.ca.gov