Engine/Drivetrain

The High-Torque Solution for Big-Power E85 & Upgraded Turbo STIsThe ACT Xtreme Performance Street Sprung Clutch Kit (SB10-XTSS) is built for the high-horsepower enthusiast who needs serious holding capacity but refuses to deal with the harsh...

The Ultimate Big-Power Option for Street & Track WRX BuildsThe ACT Xtreme Performance Street Sprung Clutch Kit (SB11-XTSS) is engineered specifically for high-powered, turbo Subarus pushing past the limits of a standard heavy-duty clutch. Pairing...

The Gold Standard for Track & Daily STI BuildsThe ACT Heavy Duty Performance Street Sprung Clutch Kit (SB10-HDSS) is the ultimate clutch upgrade for the 2.5L EJ257-powered Subaru WRX STI. Purpose-built to handle aggressive street driving, heavy...

The Definitive Daily-Driver Clutch UpgradeIf you are running an aggressive street build, a full-bolt-on setup (FBO), or an upgraded flex-fuel map, your stock Subaru clutch won't survive for long. The ACT Heavy Duty Performance Street Sprung Clutch Kit...

Maximum Acceleration & Ultra-Low Inertia for Track BuildsIf you are building a dedicated track car, a high-RPM time attack weapon, or a drag car that needs to snap through gears as fast as physically possible, the ACT XACT Prolite Flywheel (600240)...

Quicker Throttle Response Without Sacrificing DrivabilityThe ACT XACT Streetlite Flywheel (600235) is the ideal lightweight upgrade for daily-driven or spirited street Subaru STIs. Weighing in at 15.6 lbs (a significant reduction compared to heavy stock...

The Ultimate Insurance Policy for High-Performance DrivetrainsWhen you drop in a heavy-duty clutch or a lightweight chromoly flywheel, upgrading your flywheel hardware isn't just an afterthought—it's mandatory safety. Standard factory flywheel...

The $4 Lifesaver of Your Transmission InstallThere is nothing worse than fighting a heavy transmission bellhousing on a transmission jack because your clutch disc is off by a single millimeter. The ACT Clutch Alignment Tool (AT90) is a simple,...

Small Component. Massive Responsibility.Weighing in at just a fraction of a pound, the ACT Clutch Pilot Bearing (PB1004) is arguably the most critical "while you're in there" replacement part in your entire drivetrain. Pressed directly into the center...

The Absolute Cure for Pull-Type Clutch SeparationIf you drive a manual-transmission Subaru STI, an early 2.0L WRX, or an Evolution VIII/IX/X, you are likely familiar with the unique quirks of a pull-type clutch system. In a standard factory setup, the...

Smooth Engagement, Shift After ShiftThe ACT Clutch Release Bearing (RB601), commonly known as a throwout bearing (TOB), is a premium, high-quality component engineered to ensure flawlessly smooth clutch disengagement. Often overlooked during a...