ACT 19-25 Mazda MX-5 Miata Heavy Duty Performance Street Sprung Clutch Kit w/ Flywheel
Own a 2019-or-newer MX-5 Miata or Miata RF with the 2.0L and a stick, and the clutch has started to slip on a hard pull through third, judder when you leave a light, or feel soft after track days? The ACT ZM14-HDSS is a complete street clutch package for the later ND car: Heavy Duty pressure plate, organic sprung disc, and a lightweight XACT Streetlite flywheel in one box, so the whole friction stack is replaced and matched at once.
The clutch is the only thing coupling the 2.0L to the six-speed. When the factory disc glazes or the diaphragm spring loses clamp, power leaks out as heat instead of reaching the wheels. ACT rates the ZM14-HDSS at 312 ft-lb at the crank, which it lists as 46 percent more torque capacity than the original clutch. The MZ033 Heavy Duty pressure plate adds clamp load, while the 3000212 Performance Street disc keeps a sprung hub and copper-rich organic facing, so takeoff stays smooth in traffic. ACT describes the feel as light to moderate pedal effort with OE to mild gear rattle.
The flywheel matters here. ACT states this kit must be used with its own flywheel, and the 601330 Streetlite is included. It is chromoly steel at 14.1 lb with a 225 mm friction face and 112 teeth, built specifically for the ZM14 kits, so the engine revs more freely between shifts.
Do a slip check: in fourth gear around 2,500 rpm, go to full throttle. If rpm rises faster than speed, the clutch is slipping. Before pulling the transmission, look for oil at the bellhousing seam (a rear main or input seal leak will contaminate any new disc), and check that the clutch hydraulics are full and free of air. A soft pedal or a leaking slave cylinder can feel like a failed clutch. Our slipping diagnosis guide walks through separating real slip from other drivetrain faults, and the manual repair cost guide shows what the labor side of a clutch job usually costs.
This listing covers the 2019-2025 Mazda MX-5 Miata 2.0L, soft top and RF. ACT's own application chart for ZM14-HDSS runs through the 2026 model year as well, covering Club, Sport, Grand Touring and the special editions with the 1998cc engine. It does not fit the 2016-2018 car, which uses a different pressure plate and flywheel; owners of those years want the ACT ZM10-HDSS instead. Automatic cars are not covered. If you are unsure which ND you have, send us the year and VIN before ordering.
If you want sharper engagement for a track-focused car and can live with more gear rattle, ACT's rigid-hub ZM15-HDSD kit is the alternative for the same years.
| Brand | ACT |
| Part number | ZM14-HDSS |
| Fits | ACT 19-25 Mazda MX-5 Miata Heavy Duty Performance Street Sprung Clutch Kit w/ Flywheel |
| Vehicle fitment | Mazda Mx-5 Miata (2019-2025) |
| Type | Clutch Kits - Single |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
No. ACT lists ZM14-HDSS for 2019-and-later 2.0L cars only. The 2016-2018 MX-5 uses the ZM10-HDSS kit with a different flywheel and pressure plate.
Yes. The kit includes ACT's 601330 XACT Streetlite flywheel, and ACT states the clutch must be used with that ACT flywheel.
ACT says its Heavy Duty pressure plates typically raise pedal effort 15 to 40 percent depending on the car. It describes this kit as light to moderate effort.
The kit already includes the release bearing, pilot bearing and alignment tool. Fix any rear main or input seal leak while the transmission is out, and refresh the clutch fluid when you bleed it.
ACT recommends 300 to 500 miles of mild engagement, such as city driving, before racing or spirited driving with its organic street discs.
