Fitment Information:
This ACT 4 - Puck Sprung Race Disc fits a range of Subaru models. It's suitable for 2004 - 2021 Subaru STI, 2006 - 2021 Subaru WRX, 2005 - 2012 Subaru Legacy GT, 2005 - 2009 Subaru Outback XT, and 2006 - 2008 Subaru Forester XT. Note: It's a 240mm upgrade, and you must use an ACT 240mm pressure plate and flywheel.
Features:
The ACT 4 - Puck Sprung Race Disc (model 4240518) for your Subaru Impreza WRX STI is crafted from high - quality ceramic friction materials. It has a 4 - pad spring - centered design. The engagement is aggressive, which means faster shifting, though it's harsher compared to standard discs. The heavy - duty torsional dampening springs are stronger than standard ones and are sized and rated perfectly for the application. It features a heat - treated spring steel drive plate, making it ideal for smaller disc sizes in smaller engines.
- Feel: Aggressive engagement gives you quick shifts, with a bit of gear rattle similar to OE to mild setups.
- Recommended Use: This disc is only for race use.
- ACT Difference: It has high burst strength and can hold 28% more torque than typical organic materials.
- Manufacturer Warranty: Comes with a limited retail warranty.
- Installation Instructions: Follow ACT's general installation instructions.
Can it be used for daily driving?
ACT's race discs are very aggressive and offer no - nonsense performance. However, the engagement is harsh, and taking off from a stop can cause judder and noise. This type of disc should only be used in a professional race setting, not on the street. ACT recommends using an organic disc on the street for smoother engagement and longer - lasting performance for daily drivers.
When to replace the clutch disc?
Most new discs are 0.312 - 0.315 inches (7.93 - 8.00mm) thick, and they should be replaced when they reach 0.275 inches (7.00mm) or less. Some applications (mostly Audi and BMW) start at 0.332 - 0.335 inches (8.43 - 8.50mm) and should be replaced below 0.295 inches (7.50mm). Measure with a micrometer. Puck discs are measured as is, while organic street discs should be measured with the engagement cushion fully compressed. If the lining rivets on the disc touch the flywheel or pressure plate, replace the disc. Using a disc outside the pressure plate's designed working range can lead to poor results.
Using the ACT 4 - Puck Sprung Race Disc: This disc is made for racing. When installing, follow ACT's general installation instructions. Make sure to use an ACT 240mm pressure plate and flywheel as it's a 240mm upgrade. During a race, you'll notice fast shifts due to its aggressive engagement. But don't use it on the street as it can cause a harsh driving experience with judder and noise. Maintenance: Check the disc thickness regularly with a micrometer. Replace the disc when it reaches the specified minimum thickness. Also, keep an eye on the lining rivets; if they touch the flywheel or pressure plate, it's time for a new disc. This will help keep your clutch and drive line components in good shape.
