Clutch Masters 06-08 Subaru WRX 2.5L Eng. 5-Spd FX300 Clutch Kit
The Clutch Masters 15021-HDTZ is an FX300 clutch kit for the 2.5L turbo Subaru WRX with the 5-speed manual, listed here for the 2006-2008 cars. These WRXs are famous for clutches that start to slip once the EJ255 gets an access-port tune, a downpipe or a bigger turbo. If yours flares RPM in fourth under boost, smells hot after a spirited drive, or engages at the very top of the pedal, the FX300 is the step that holds the extra torque without turning the car into a race-only build.
Clutch Masters builds the FX300 around its Power Plus I heavy duty pressure plate and a steel-backed disc with segmented Kevlar facing. The segments concentrate clamp load on a smaller friction area, which raises pressure per square inch and lets the disc hold more torque while the Kevlar still wears slowly. Clutch Masters rates this stage at 110 percent more holding capacity than stock and aims it at street cars with medium boost, not track cars. Pedal pressure goes up only slightly, engagement is positive, and the Kevlar is non-abrasive on the flywheel. It is a strong match for a Stage 2 style WRX that still sees traffic every day.
The kit includes the pressure plate, a sprung-hub disc with a marcel spring wafer, a release bearing, an alignment tool, an instruction card and decals. A pilot bearing is included only where the application uses one, and no flywheel comes in the box.
Run a fourth-gear full-throttle pull from about 2,500 RPM. If the tach rises faster than the speedometer once the turbo spools, the disc is slipping. Our slip diagnosis guide explains the test, and flare vs. slip helps if you are not sure what you are feeling. Also rule out a dragging or sticking hydraulic system; our pedal engagement page covers what a high or low engagement point really means.
Our listing covers the 2006-2008 Subaru WRX 2.5L turbo 5-speed. Clutch Masters lists 15021-HDTZ more broadly, for the 2006-2014 WRX 2.5L turbo 5-speed and for 5-speed Legacy GT applications. It does not fit the WRX STI, which uses the 6-speed and a different clutch. Clutch parts on these cars changed between the 2002-2005 2.0L WRX and the 2006-up 2.5L car, so do not use this kit on an earlier WRX. If you have a 2009-2014 WRX, a Legacy GT, or a swapped car, send us the year and full VIN and we will confirm the match before it ships.
If your car is lightly modified and you want the smoothest engagement, look at the FX200 15021-HDKV for the same 5-speed. Running more boost? The FX350 kit steps up holding power.
| Brand | Clutch Masters |
| Part number | 15021-HDTZ |
| Fits | Clutch Masters 06-08 Subaru WRX 2.5L Eng. 5-Spd FX300 Clutch Kit |
| Vehicle fitment | Subaru Wrx (2006-2008) |
| Type | Clutch Kits - Single |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Clutch Masters lists 15021-HDTZ for the 2006-2014 WRX 2.5L turbo 5-speed, while our listing is titled for 2006-2008. Send us your VIN for a 2009-up car and we will confirm before shipping.
No. The STI uses a 6-speed with its own clutch. This kit is for the non-STI 2.5L turbo 5-speed WRX.
Clutch Masters rates it at 110 percent more holding capacity than stock and recommends it for medium-boost street cars, not track use. For bigger turbos or frequent launches, look at the FX350.
A flywheel is not included. At minimum have yours resurfaced; replace it if it is heat-cracked, blued or below minimum thickness.
Clutch Masters requires a minimum 500-mile break-in. Avoid launches and full-boost pulls until then.
