The SB10-HDG6 kit pairs ACT's most popular Heavy Duty pressure plate with a 6-pad spring-centered race disc and ACT's Monoloc release system, sized for the EJ257 turbo platform in the Subaru WRX STI and Legacy GT spec.B. The Heavy Duty pressure plate uses ACT's exclusive diaphragm design to increase clamp load, reduce deflection, and extend clutch life; every diaphragm goes through a four-stage heat-treating process, and cover stampings are precision-made for rigidity and consistency. The 6-pad spring-centered race disc damps torsional vibration and resists failure under hard use, with wraparound spring windows and thicker retainer stampings for added strength. Monoloc is a one-piece, direct replacement for the standard two-piece wedge collar and wire ring used in pull-type clutches; its carefully calculated spring tension gives uniform loading on the bearing and pressure plate for consistent alignment, and its hardened chrome-moly steel construction is built for years of service.
WarrantyInstallation Instructions
- Backed by ACT's one-year "Excellence in Performance" warranty
Specifications
- Pressure Plate: ACT Heavy Duty, four-stage heat-treated diaphragm, precision cover stamping
- Disc: 6-pad spring-centered race disc
- Release System: Monoloc one-piece hardened chrome-moly retaining ring
- Recommended Use: Race and aggressive street driving; recommended for larger clutch sizes needing to absorb more heat
- Part Number: SB10-HDG6
Vehicle Applications
| Year | Make | Model | Trim |
|---|---|---|---|
| 2004 | Subaru | Impreza | WRX STI |
| 2005 | Subaru | Impreza | WRX STI |
| 2006 | Subaru | Impreza | WRX STI |
| 2007 | Subaru | Impreza | WRX STI |
| 2008 | Subaru | Impreza | WRX STI |
| 2009 | Subaru | Impreza | WRX STI |
| 2010 | Subaru | Impreza | WRX STI |
| 2011 | Subaru | Impreza | WRX STI |
| 2012 | Subaru | Impreza | WRX STI |
| 2013 | Subaru | Impreza | WRX STI |
| 2014 | Subaru | Impreza | WRX STI |
| 2007 | Subaru | Impreza | WRX STI Limited |
| 2011 | Subaru | Impreza | WRX STI Limited |
| 2012 | Subaru | Impreza | WRX STI Limited |
| 2013 | Subaru | Impreza | WRX STI Limited |
| 2014 | Subaru | Impreza | WRX STI Limited |
| 2010 | Subaru | Impreza | WRX STI Special Edition |
| 2007 | Subaru | Legacy | GT spec.B |
| 2008 | Subaru | Legacy | GT spec.B |
| 2009 | Subaru | Legacy | GT spec.B |
| 2015 | Subaru | WRX STI | Base |
| 2016 | Subaru | WRX STI | Base |
| 2017 | Subaru | WRX STI | Base |
| 2018 | Subaru | WRX STI | Base |
| 2019 | Subaru | WRX STI | Base |
| 2020 | Subaru | WRX STI | Base |
| 2021 | Subaru | WRX STI | Base |
| 2015 | Subaru | WRX STI | Launch Edition |
| 2015 | Subaru | WRX STI | Limited |
| 2016 | Subaru | WRX STI | Limited |
| 2017 | Subaru | WRX STI | Limited |
| 2018 | Subaru | WRX STI | Limited |
| 2019 | Subaru | WRX STI | Limited |
| 2020 | Subaru | WRX STI | Limited |
| 2021 | Subaru | WRX STI | Limited |
| 2019 | Subaru | WRX STI | S209 |
| 2016 | Subaru | WRX STI | Series.HyperBlue |
| 2018 | Subaru | WRX STI | Type RA |
FAQ
What is Monoloc and why does it matter?
Monoloc is ACT's one-piece hardened chrome-moly release ring that replaces the stock two-piece wedge collar and wire ring on pull-type clutches, giving more consistent bearing/pressure-plate alignment regardless of driver input or vehicle modifications.
Does this kit fit both the STI and Legacy GT spec.B?
Yes, SB10-HDG6 is sized for the shared EJ257 turbo platform used in both the Impreza/WRX STI and the Legacy GT spec.B, as listed in the Vehicle Applications table.
Is this kit streetable?
It can be driven on the street, but engagement is firmer than a street disc; it suits drivers who want faster shifting and more heat capacity and can tolerate more driveline feel.
What's included in the kit?
The kit includes the ACT Heavy Duty pressure plate, the 6-pad spring-centered race disc, and the Monoloc release ring sized for this application.