Heavy Duty Clamp Load With Street-Friendly Engagement
The ACT ZM15-HDSD steps up holding capacity for the ND2 Miata while keeping engagement manageable for daily street driving. This kit pairs a Heavy Duty pressure plate with a rigid full-face performance disc, delivering a 46 to 87 percent increase in torque capacity over the factory clutch depending on the specific build. Unlike a sprung race disc, the ZM15-HDSD’s rigid hub is built for street and light performance use, giving a more direct pedal feel without the segmented chatter of a full race disc. The kit ships with a chromoly XACT Streetlite flywheel so the entire assembly is matched and balanced from the factory.
Key Features
- ZM15-HDSD combines a Heavy Duty pressure plate with a rigid performance disc for increased torque capacity
- 46 to 87 percent increase in torque holding capacity over the stock ND2 Miata clutch
- Rigid hub design for a direct pedal feel in street and performance driving
- Includes a chromoly XACT Streetlite flywheel matched to the ZM15-HDSD kit
- Positioned for daily-driven and lightly modified ND2 Miata builds
Fitment
| Year Range | Make | Model | Trim |
|---|---|---|---|
| 2020 | Mazda | MX-5 Miata | 100th Anniversary SE |
| 2025 | Mazda | MX-5 Miata | 35th Anniversary |
| 2019-2025 | Mazda | MX-5 Miata | Club |
| 2019-2025 | Mazda | MX-5 Miata | Grand Touring |
| 2020 | Mazda | MX-5 Miata | RF 100th Anniversary SE |
| 2019-2025 | Mazda | MX-5 Miata | RF Club |
| 2019-2025 | Mazda | MX-5 Miata | RF Grand Touring |
| 2019-2025 | Mazda | MX-5 Miata | Sport |
Specifications
| Detail | Value |
|---|---|
| MPN | ZM15-HDSD |
| Design | Heavy Duty pressure plate, rigid performance street disc |
| Hub Type | Rigid |
| Torque Capacity Increase | 46 to 87 percent over stock |
| Flywheel Included | Chromoly XACT Streetlite |
| Platform | ND2 Miata |
What’s Included
- 1x ZM15-HDSD Heavy Duty pressure plate with rigid performance street disc
- 1x Chromoly XACT Streetlite flywheel
- Clutch hardware, release bearing, pilot bearing, and alignment tool
About ACT
Advanced Clutch Technology (ACT) designs the ZM15-HDSD as a Heavy Duty street and performance option for the ND2 Miata, giving drivers more torque capacity than stock while keeping clutch engagement suitable for regular street use.
Related Parts
- ACT 07-11 Mazdaspeed 3 Performance Street Sprung Disc
- ACT 2006 Mazda 6 Perf Street Sprung Disc
FAQ
What is the ZM15-HDSD?
The ZM15-HDSD is an ACT Heavy Duty pressure plate paired with a rigid performance street disc and matched chromoly flywheel, built for the ND2 Mazda MX-5 Miata to increase torque capacity while remaining street driveable.
How much torque capacity does the ZM15-HDSD add?
The ZM15-HDSD provides a 46 to 87 percent increase in torque holding capacity over the factory ND2 Miata clutch, depending on the specific vehicle and driving conditions.
Does the ZM15-HDSD include a flywheel?
Yes, the ZM15-HDSD kit includes a chromoly XACT Streetlite flywheel matched to the clutch assembly, along with hardware, release bearing, pilot bearing, and alignment tool.
Is the ZM15-HDSD suitable for daily driving?
Yes, the ZM15-HDSD is positioned as a Heavy Duty street and performance clutch, designed to keep engagement manageable for daily driving while adding torque capacity over the stock clutch.
What is the difference between the ZM15-HDSD and the ZM14-HDG6?
The ZM15-HDSD uses a rigid full-face disc for direct engagement suited to street use, while the ZM14-HDG6 uses a segmented 6-pad sprung race disc built for autocross, track, and drag applications.
Which Miata trims does the ZM15-HDSD fit?
The ZM15-HDSD fits ND2-generation MX-5 Miata trims including Sport, Club, Grand Touring, RF Club, RF Grand Touring, and the limited-run 100th and 35th Anniversary Editions.
Does the ZM15-HDSD fit an NA or NB Miata?
No, the ZM15-HDSD is engineered for the ND2-generation Miata’s clutch and flywheel dimensions and is not listed as a fit for earlier NA or NB chassis.
Does the ZM15-HDSD have a harsher pedal feel than stock?
The ZM15-HDSD’s rigid hub and Heavy Duty pressure plate produce a firmer, more direct pedal feel than the factory clutch, though it remains within ACT’s street-driveable Perf Street rigid product line.
Install Instructions
- Remove the transmission from the vehicle following the factory service procedure for the ND2 Miata.
- Remove the factory flywheel, pressure plate, and clutch disc from the crankshaft flange.
- Install the ZM15-HDSD chromoly XACT Streetlite flywheel and torque the mounting bolts to factory specifications.
- Center the ZM15-HDSD rigid disc using the supplied alignment tool, then bolt on the Heavy Duty pressure plate.
- Install the new pilot bearing and release bearing included with the ZM15-HDSD kit.
- Reinstall the transmission, reconnect the hydraulic clutch line, and bleed the clutch system before test driving.
Prop 65 Warning
This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.








