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Action Clutch Chromoly Lightweight Flywheel 2004 - 2021 STI / 2007 - 2009 Legacy GT - AC117FW - Subimods.com

Action Clutch Chromoly Lightweight Flywheel 2004-2021 STI

$331.46
$389.95
$389.95 - $389.95
$389.95
$331.46 - $331.46
$331.46
-15% -15%
Only 2 Left In Stock! Usually Ships within 1-2 Business Days
SKU AC117FW
by Action Clutch
Lease to own Pay as low as $/week

DETAILS

Action Clutch Chromoly Lightweight Flywheel 2004-2021 STI | Performance Enhancement | Drivetrain Upgrade

Overview

The Action Clutch Chromoly Lightweight Flywheel is a high-performance upgrade designed specifically for Subaru WRX STI models from 2004 to 2021. This flywheel reduces rotational mass, resulting in quicker engine response, sharper throttle feel, and improved acceleration. It’s an ideal choice for enthusiasts looking to enhance their vehicle’s responsiveness, whether for street driving, spirited canyon runs, or competitive racing. Crafted from premium Chromoly steel, this flywheel offers a perfect balance of strength, durability, and weight savings, making it a reliable upgrade that can handle the demands of high-revving turbocharged engines.

Built with a focus on engineering excellence, the Action Clutch flywheel undergoes specialized heat treatment to withstand extreme thermal loads and high RPMs, tested up to 18,000 RPM. Its resurfacable surface extends the lifespan of the component, providing excellent value for long-term use. While the reduced mass improves throttle response and acceleration, it may introduce increased noise, vibration, and harshness (NVH), a common trade-off in lightweight flywheel designs. Subaru owners who seek a more engaging driving experience will appreciate the direct feel and improved drivetrain durability this product offers. As a community-focused brand, Subimods is proud to offer parts that are tailored specifically for Subaru enthusiasts, ensuring perfect fitment and performance gains.

Features & Specifications

This Action Clutch flywheel is engineered for Subaru WRX STI models and features a lightweight design that enhances engine responsiveness and durability. Constructed from high-strength Chromoly steel, it delivers a significant reduction in rotational mass for quicker revs and sharper throttle response, ideal for tuning and performance driving.

  • Brand: Action Clutch
  • Product: Chromoly Lightweight Flywheel 2004-2021 STI
  • Part Number: Not specified
  • Fitment: Subaru WRX STI (2004-2021)
  • Material: Chromoly Steel
  • Finish: Natural Steel Finish
  • Construction: CNC Machined, Heat Treated
  • Origin: Made in USA
  • Weight: 15.5 lbs
  • Tested Up To: 18,000 RPM
  • Standards: Meets SFI 1.1 safety standards
  • Resurfacable: Yes

Key Benefits

  • Enhanced Performance: Significantly improves throttle response and acceleration, making your STI more lively and engaging to drive.
  • Durability & Reliability: Crafted from high-strength Chromoly steel with heat treatment, designed to withstand high thermal loads and aggressive driving conditions.
  • Weight Savings: Reduces rotational mass to enable quicker revs, beneficial for tuning and track use.
  • Long-Term Value: Resurfacable surface extends lifespan, saving money on replacements over time.
  • Safety & Quality: Meets SFI 1.1 standards, ensuring safety during high-RPM operation.
  • Community-Driven Design: Specifically engineered for Subaru enthusiasts seeking a reliable drivetrain upgrade.

What's Included

  • 1× Action Clutch Chromoly Lightweight Flywheel
  • Installation hardware (if applicable)
  • Resurfacing instructions

Installation & Compatibility

This lightweight flywheel is designed for direct bolt-on installation on 2004-2021 Subaru WRX STI models. While the installation process is straightforward for experienced DIYers with basic tools, we recommend professional installation to ensure proper torque specifications and safety. The reduced mass may increase NVH levels slightly, which is typical for lightweight flywheel setups. Tuning adjustments, such as clutch engagement and idle settings, may be necessary to optimize performance. Always verify fitment for your specific vehicle year and trim to ensure compatibility.

  • Professional Installation: Recommended for best results
  • Modifications Required: None, direct bolt-on
  • Verify Compatibility: Confirm fitment for your specific year and model
Which Action Clutch Kit is Right for You? 

Choosing the right clutch comes down to how you drive and how much power you're putting down.

Stage 1 OEM+: The perfect OEM+ upgrade—feels like stock but handles more power. Great for daily drivers who want a smooth engagement with a performance boost. High levels of our copper blend friction mix for high heat resistance. 500 mile break in is necessary for optimal performance.

Stage 1 HD Street: Suited for vehicles with full bolt-ons and E85, with a 15% heavier pedal feel for a performance response while keeping things street-friendly. 500 mile break in is necessary for optimal performance.

Stage 2 Endurance: just cruising? Or driving a lot in traffic? This kit is designed for longevity and reliability. Our Bullet Proof-Kevlar friction disc is built to last. Perfect for daily drivers, basic bolt-on mods, and occasional spirited track driving. This kit lasts twice as long as an OEM depending on your drivability. 1000 mile break in is necessary for optimal performance.

Stage 3 Track-Tuned: Built for drivers who want serious performance. A sprung 6-puck disc with MIBA Ceramic friction buttons delivers quick engagement, has high-heat resistance levels, and maximum grip—ideal for aggressive street driving, weekend track days, and serious builds. 500 mile break in is necessary for optimal performance.

For high-horsepower builds, our Multi-Disc kits are the next level. These feature american made sintered metallic race discs, a lightweight 6061-T6 Billet Aluminum clutch cover, and high-strength steel alloy plates for fast shifts and extreme power handling. While unbeatable for racing, they’re not made for street use. Sprung options are available, incorporating our patented fully enclosed spring retainers for added durability.
All Action Clutch kits come with our Fully Enclosed Patented Ventilated Spring Retainers, designed for maximum reliability under any condition. No more worrying about springs popping out and wrecking your transmission or engine—just pure performance you can trust.
Each kit is engineered to meet OEM specs and upgraded to handle more power and match your driving style—proudly built right here in Los Angeles.

Full-Face vs. Pucked Clutch: Which One is Right for You? 

A full-face disc is best for daily driving and street applications, offering smooth engagement, longevity, and consistent performance. Its larger friction surface helps with heat distribution, making it ideal for vehicles with mild to moderate power upgrades while maintaining a comfortable pedal feel. A pucked clutch, on the other hand, is built for high-performance driving, providing quick engagement, superior heat resistance, and increased torque capacity. It’s the preferred choice for racing, drifting, and aggressive driving, but comes with a more abrupt engagement and a firmer pedal feel. If you want a comfortable, long-lasting clutch for the street, go with a full-face disc. If you need faster shifts and durability under extreme conditions, a pucked clutch is the better choice. Action Clutch offers both to match your driving needs.

What’s the Added Benefit of Action Clutch’s Fully Enclosed PATENT Spring Retainers? 

Our Patented Fully Enclosed Ventilated Spring Retainers are designed to prevent spring ejection under extreme use, a common failure seen in many competitor clutch kits. If a spring ejects, it can cause catastrophic damage to the clutch and potentially harm the engine or transmission, leading to expensive repairs. Traditional open-style spring retainers allow springs to shift, dislodge, or break under aggressive driving conditions, increasing the risk of failure. By fully enclosing the springs, our design eliminates this risk, ensuring maximum durability and consistent performance even under extreme stress. Even in the rare event of a spring failure, it remains contained within the retainer, allowing you to continue using the clutch for its full lifespan. This added protection enhances longevity, reliability, and overall performance, making it ideal for daily driving, track use, and high-torque applications. With Action Clutch, you get the peace of mind that your clutch is built to withstand the most demanding conditions.

What’s the Difference Between an OEHD and a Chromoly Lightweight Flywheel? 

The choice between an OEHD (Original Equipment Heavy Duty) Flywheel and a Chromoly Lightweight Flywheel depends on your driving style and performance goals. Our OEHD Flywheels are constructed from Ductile Iron, offering maximum durability, heat resistance, and longevity. This reinforced design maintains an OEM-like driving experience with smooth engagement, minimal noise, and increased resilience, making it ideal for daily drivers, street applications, and vehicles needing a reliable, heavy-duty replacement. In contrast, our Chromoly Lightweight Flywheels are engineered for performance-focused driving, significantly reducing rotational mass to allow faster revs, improved throttle response, and quicker acceleration. Made from high-strength chromoly steel, these flywheels are ideal for track use, spirited driving, and high-performance builds. While they enhance performance, they may lead to quicker clutch engagement and slight increases in drivetrain noise, which some drivers may notice in daily driving. If you prioritize smooth engagement, longevity, and durability, an OEHD Flywheel is the best choice. If you're looking for faster engine response and enhanced performance, a Chromoly Lightweight Flywheel is the way to go. Action Clutch offers both to match your specific driving needs.

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Chromoly Lightweight Flywheels – Faster Revs, Sharper Response

When every millisecond counts, Action Clutch Chromoly Lightweight Flywheels deliver the quick throttle response and high-rev performance you need to stay ahead. Designed for track warriors, spirited drivers, and high-performance builds, these flywheels reduce rotational mass, allowing your engine to rev faster, shift quicker, and accelerate harder. Crafted from high-strength chromoly steel, our lightweight flywheels provide exceptional durability, heat resistance, and consistent performance under extreme conditions. Whether you're launching off the line or powering through corners, you’ll feel the improved responsiveness and smoother downshifts that set Action Clutch apart. Built for track, street, and everything in between, our Chromoly Lightweight Flywheels let your engine unleash its full potential—faster, stronger, and more precise. Less weight. More power. Maximum performance.

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Chromoly Lightweight Flywheels – High-Performance Gains with Trade-Offs

For drivers looking to maximize engine response and acceleration, Action Clutch Chromoly Lightweight Flywheels are built to reduce rotational mass, allowing for faster revs, quicker shifts, and improved throttle response. Designed for track, street, and high-performance applications, these flywheels provide enhanced engine efficiency and a more connected driving experience. Made from high-strength chromoly steel, these flywheels offer exceptional durability and heat resistance, making them ideal for hard launches, high-RPM shifts, and extreme conditions. However, due to their lighter weight, they may result in a slightly rougher idle, increased drivetrain noise, and require more effort to launch from a stop in some setups. If you’re after lightning-fast revs and maximum performance, Action Clutch Chromoly Lightweight Flywheels give you the edge to push your build further. Less weight. More power. Maximum performance.

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