Clutch Masters Lightened Flywheel

2004–2021 Subaru Impreza WRX STI 2.0L / 2.5L Turbocharged Engines

Part #: FW-721-AL

Overview

The Clutch Masters Lightened Flywheel is a high-performance upgrade designed specifically for Subaru STI models from 2004 to 2021. Engineered to reduce the rotational mass of your vehicle's crankshaft, this flywheel enhances acceleration, throttle response, and overall driving dynamics. Whether you're a street enthusiast, a spirited driver, or a motorsport competitor, this lightweight flywheel offers tangible benefits that improve your Subaru's performance.

By decreasing the weight of the flywheel, you'll experience quicker engine spool-up and reduced turbo lag in turbocharged models. Supercharged engines also benefit from the increased efficiency by minimizing parasitic drag on the crankshaft, leading to more responsive power delivery. Naturally aspirated engines can enjoy improved mid-range torque, making daily driving and spirited runs more enjoyable. This upgrade is ideal for drivers seeking a more engaging driving experience without sacrificing reliability or drivability.

Key Features

The Clutch Masters lightweight flywheel incorporates advanced materials and precise engineering to deliver superior performance and durability. Key features include:

• Constructed from high-quality, heat-treated aluminum alloy for optimal strength-to-weight ratio.
• Significantly reduced rotating mass compared to stock flywheels, resulting in faster engine response and acceleration.
• Designed specifically for turbocharged, supercharged, and naturally aspirated Subaru engines, enhancing mid-range torque and throttle response.
• Precision-machined for perfect fitment and smooth operation, ensuring reliable clutch engagement and longevity.
• Compatible with stock and aftermarket clutches, providing flexibility for various driving styles and performance goals.
• Engineered to withstand high RPMs and aggressive driving conditions, maintaining structural integrity over time.
• Easy bolt-on installation with no need for modifications or special tools, making it a straightforward upgrade.

Construction & Design

The flywheel features a one-piece aluminum construction with CNC-machined surfaces for precise fitment and balance. Its lightweight design reduces inertia, allowing the engine to rev more freely and respond more quickly to throttle inputs. The use of high-quality materials ensures durability under demanding driving conditions, while the heat-treated alloy helps resist warping and cracking. The design also minimizes vibrations and noise, contributing to a smoother driving experience.

Installation & Fitment

The Clutch Masters Lightened Flywheel is a direct bolt-on replacement for the stock flywheel on compatible Subaru STI models from 2004 to 2021. No cutting, drilling, or special tuning is required for installation. It is recommended to inspect and possibly upgrade your clutch components when installing a lightweight flywheel to ensure optimal performance and longevity. Professional installation is advised to guarantee proper alignment and torque specifications.

• Easy, bolt-on installation with standard tools
• No modifications needed
• Compatible with stock and aftermarket clutch kits

What's Included

• Lightened aluminum flywheel
• Installation hardware and bolts
• Instruction manual

Ideal For

• Subaru STI owners seeking improved acceleration and throttle response
• Performance enthusiasts looking to reduce turbo lag and mid-range torque loss
• Drivers wanting a more engaging and responsive driving experience
• Motorsport competitors requiring lightweight, durable flywheel solutions