SKU: FW-721-AL
Clutch Masters 04-08 Subaru WRX STI 2.5L 6-Spd Aluminum Flywheel
Upgrade your Subaru WRX STI with the Clutch Masters FW-721-AL aluminum flywheel, designed for 2004-2008 models with 2.5L engine and 6-speed transmission. This lightweight component drops rotational mass from stock 22.2 lbs to 11.4 lbs, delivering faster engine response, quicker acceleration, and precise shifts during aggressive driving. Perfect for street, track, or rally applications where every ounce counts.
Key Features
- Lightweight Aluminum Build: Reduces mass by nearly 50% versus OEM steel flywheel for immediate throttle response and reduced drivetrain stress
- SFI 1.2 Certification: Meets strict safety standards for high-RPM racing with proven durability under extreme heat and abuse
- Electron Beam Welded Ring Gear: Heat-treated steel gear ensures long-lasting tooth engagement and resists wear in high-torque setups
- Black Anodized Finish: Corrosion-resistant coating maintains appearance and dissipates heat effectively during hard use
- Precision Balanced: Factory-balanced to OEM specs to eliminate vibrations and support compatibility with stock or performance clutches
Product Notes
- This is a special order item, allow 3-5 business days for processing
- Pair with Clutch Masters clutch kits for best results in high-horsepower builds
- Ships in secure foam-lined box measuring 14" x 14" x 6" with 13 lb shipping weight
Installation Notes
- Professional installation recommended.
- Requires Subaru-specific pilot bearing and throwout bearing for proper operation
- Compatible with OEM and aftermarket clutch assemblies, no flywheel resurfacing needed
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2004-2014 | Subaru | Impreza | WRX STI |
| 2007,2011-2014 | Subaru | Impreza | WRX STI Limited |
| 2010 | Subaru | Impreza | WRX STI Special Edition |
| 2007-2009 | Subaru | Legacy | GT spec.B |
| 2015-2017 | Subaru | WRX STI | Base |
| 2015 | Subaru | WRX STI | Launch Edition |
| 2015-2017 | Subaru | WRX STI | Limited |
| 2016 | Subaru | WRX STI | Series.HyperBlue |
Why Choose Clutch Masters?
- Backed by decades of racing wins in drag, road, and rally series
- Uses aerospace-grade aluminum and steel for reliable high-heat performance
- Engineered and balanced in Southern California for exact OEM fitment
Frequently Asked Questions
-
Q: Does this flywheel fit 2004-2008 WRX STI 6-speed only?
A: Yes, FW-721-AL is direct fit for 2004-2008 Subaru Impreza WRX STI 2.5L with 6-speed manual, plus select later STI models listed in fitment -
Q: What material is the flywheel made from?
A: 6061-T6 aircraft aluminum body with heat-treated steel ring gear, black anodized for heat and corrosion resistance -
Q: What is the warranty and installation details?
A: Limited lifetime warranty against defects. Install requires torque specs per Subaru service manual, professional shop advised for alignment
Shipping & Handling
- Method: UPS Ground or FedEx, free over $99
- Availability: In stock - ships same or next business day
- Packaging: Foam-lined box, 14 x 14 x 6 inches
- Weight: 11.4 lbs product, 13 lbs shipped
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