Upgrading your vehicle’s flywheel is one of the most effective ways to sharpen engine response and improve acceleration. A lightweight performance flywheel reduces rotational mass, allowing your engine to rev more freely and recover more quickly between shifts. This modification is a favorite among driving enthusiasts and competitive racers looking for that extra edge in performance and drivability.
Choosing the right flywheel, however, depends on your specific vehicle, goals, and whether you need a standalone component or a complete clutch kit. To help you make an informed decision, we have compiled a detailed roundup of top-rated ACT flywheels and compatible kits. Our reviews focus on the construction, benefits, and ideal use cases for each product to guide you toward the perfect upgrade for your ride.
Top ACT Flywheels and Clutch Kits
- ACT 600585 XACT Prolite Flywheel
- ACT 600350 XACT Prolite Flywheel
- ACT SB11-HDSS Clutch Kit with Streetlite Flywheel
- ACT 600105 ProLite Xact Flywheel
- ACT HC12-HDG6 Heavy Duty Race Clutch Kit
- ACT 600235 Street Lite Flywheel
- Action Clutch Chromoly Flywheel for Nissan 350Z/370Z
- ACT SB11-XTSS Clutch Kit with Streetlite Flywheel
- XTD Stage 3 Clutch & Pro-Lite Flywheel Kit
- ACT Pro-Lite Flywheel for Subaru WRX/STI
ACT 600585 XACT Prolite Flywheel
The ACT 600585 XACT Prolite Flywheel is engineered for drivers seeking a significant improvement in engine response and acceleration. Its lightweight design reduces rotational mass, which allows your engine to rev more freely and recover faster between gear changes. This results in a more connected and responsive driving experience, especially in performance-oriented situations.
Durability is a key focus of this flywheel. ACT employs a rigorous manufacturing process that includes heat-treating the entire forging for enhanced strength and toughness. The ring gear is induction hardened to ensure the longest possible gear life. The one-piece construction is a critical feature, as it minimizes the opportunity for failure and provides uniform, efficient heat transfer from the clutch disc, eliminating common issues like warped inserts or loose ring gears.
ACT 600350 XACT Prolite Flywheel
Similar to its counterpart, the ACT 600350 XACT Prolite Flywheel is built to unlock your engine’s potential by shedding unnecessary weight. This model is designed for a specific vehicle application, providing the same renowned Prolite benefits of improved throttle response and quicker acceleration. It is an ideal upgrade for those looking to enhance their car’s performance without compromising reliability.
The flywheel’s construction follows ACT’s high standards, featuring a fully heat-treated forging for maximum strength and an induction-hardened ring gear for superior durability. The one-piece design is central to its performance, ensuring robust operation under stress and efficient dissipation of heat generated by the clutch. This design philosophy guarantees a component that stands up to demanding use while providing consistent performance.
ACT SB11-HDSS Clutch Kit with Streetlite Flywheel
For a complete solution, the ACT SB11-HDSS Clutch Kit bundles a heavy-duty pressure plate and a performance street disc with a Streetlite flywheel. This kit is engineered for a conversion to a 240mm setup, offering a balanced combination of increased torque capacity and improved drivability. It is an excellent choice for modified street vehicles that need a stronger clutch without an overly aggressive pedal feel.
ACT stands behind this kit with its “Excellence in Performance” guarantee, backed by a robust one-year warranty that is among the best in the industry. This package provides everything needed for a clutch replacement or upgrade in one box, ensuring all components are perfectly matched for optimal performance and longevity. It is a reliable and hassle-free way to upgrade your drivetrain.
ACT 600105 ProLite Xact Flywheel
The ACT 600105 ProLite Xact Flywheel represents the pinnacle of lightweight design from ACT. As the lightest flywheel in their lineup, it is specifically engineered to maximize engine response, making it a favorite for racing and high-performance street applications. The reduced rotational inertia allows for incredibly quick revving, which can be particularly beneficial in motorsports.
Despite its focus on minimal weight, this flywheel does not sacrifice strength or affordability. It is built using ACT’s proven manufacturing techniques to ensure it can handle the stresses of high-RPM operation. This model provides a direct path to a more responsive engine, offering a noticeable difference in how quickly the powertrain reacts to driver input.
ACT HC12-HDG6 Heavy Duty Race Clutch Kit
The ACT HC12-HDG6 is a heavy-duty race clutch kit featuring a sprung 6-puck disc, designed for serious performance. It expertly bridges the gap between street and track, offering excellent drivability for daily use while being capable of handling up to 412 ft-lb of torque. This makes it a versatile option for a powerful street car that sees occasional track duty.
For competitive environments like drag, road, or rally racing, this kit is built to withstand extreme demands. It combines a Heavy Duty Pressure Plate with a Cerametallic Xtreme Race Disc. The 6-puck, spring-centered configuration helps dampen gear noise and shock, providing a more manageable engagement compared to a rigid hub design, without compromising on grip or durability.
ACT 600235 Street Lite Flywheel
The ACT 600235 Street Lite Flywheel is designed to offer a perfect balance between performance and daily driveability. While it reduces weight for better engine response, it also retains enough mass to effectively smooth out the engine’s firing impulses. This results in a more refined driving experience compared to an ultra-lightweight flywheel, making it an excellent choice for a street-driven performance vehicle.
This flywheel provides a noticeable improvement in acceleration and throttle response without introducing excessive gear rattle or a finicky idle. It is the ideal compromise for the enthusiast who wants to enhance their car’s performance but still prioritizes smooth operation in traffic and during low-RPM driving.
Action Clutch Chromoly Flywheel for Nissan 350Z/370Z
This chromoly lightweight flywheel from Action Clutch is specifically engineered for Nissan 350Z and 370Z models with the VQ35-37 HR motor. Its low weight and reduced inertia are tailored to enhance engine response, delivering quicker revs and improved acceleration that is ideal for competitive events like drag racing, autocross, and rally.
Crafted from a durable one-piece billet chromoly steel or chromoly steel forging, this flywheel boasts a high thermal capacity. This allows it to withstand extreme heat generated during aggressive driving without warping or failing. It is rigorously tested for reliable performance at very high RPMs, ensuring durability and stability under the most intense racing conditions.
ACT SB11-XTSS Clutch Kit with Streetlite Flywheel
The ACT SB11-XTSS Clutch Kit is a step up in performance, featuring an XT (Xtreme) pressure plate paired with a performance street disc (SS) and a Streetlite flywheel. This configuration is designed for vehicles with significant power upgrades that require a higher torque capacity than a standard heavy-duty kit can provide. It offers a firm pedal feel and robust clamping force.
Like other ACT kits, this is a complete conversion package to a 240mm setup. It is engineered for drivers who need a clutch that can handle the power of a heavily modified engine while still maintaining characteristics that are manageable for street use. The included Streetlite flywheel complements the clutch by reducing rotational mass for improved engine response.
XTD Stage 3 Clutch & Pro-Lite Flywheel Kit
The XTD Stage 3 Clutch and Pro-Lite Flywheel Kit is designed for Mitsubishi Lancer Evolution models 4, 5, and 6. This complete kit offers a performance-oriented solution for drivers needing a clutch that can hold higher power levels while being paired with a lightweight flywheel for improved engine response. It is a comprehensive package for a full drivetrain upgrade.
All XTD kits are assembled in the U.S. using top-quality components and are built to OEM specifications to ensure a proper fit and function. The company also provides access to highly trained customer support to answer technical questions, which can be very helpful for DIY installers ensuring the product is installed correctly for optimal performance.
ACT Pro-Lite Flywheel for Subaru WRX/STI
This ACT Pro-Lite flywheel is specifically designed for Subaru WRX and STI models from 2002 to 2021. It brings the signature benefits of the Pro-Lite series to the Subaru platform, significantly reducing rotational mass to allow the boxer engine to rev with greater urgency and recover more quickly between shifts. This can make a noticeable difference in the car’s overall agility and responsiveness.
As with all ACT flywheels, it is constructed to the highest standards of durability and performance. The one-piece design and advanced heat treatment ensure it can handle the increased stress of performance driving and high-RPM operation. For Subaru owners looking to sharpen their car’s performance, this flywheel is a proven and reliable upgrade.
Buying Guide: How to Choose the Right ACT Flywheel
So, you are thinking about upgrading your clutch setup and an ACT flywheel is on your list. I have been through this process myself, and I can tell you that choosing the right one is not just about picking the lightest option. It is about matching the flywheel to your car, your driving style, and your goals. Let us break down what you need to consider before you commit.
First, you need to decide on the material. ACT offers flywheels in chromoly steel and pro-lite aluminum. The steel ones are the heavy-duty all-rounders. They are durable, manage heat well, and are perfect for a daily driver or a street car that sees occasional track use. The aluminum flywheels are significantly lighter. This reduces rotational mass, which means your engine can rev up faster. It feels fantastic for performance driving, but it can make daily driving a bit trickier, as you might need to give it more gas to get moving from a stop.
Next, think about weight. This is the big trade-off. A lighter flywheel, like those in the Pro-Lite series, improves throttle response and acceleration. However, it also reduces rotational inertia. In practice, this can make the car easier to stall at low RPMs and might cause a rougher idle. A heavier flywheel, like the Streetlite, provides more smoothness for stop-and-go traffic and helps with engine braking. For most people building a street-performance car, a Streetlite offers the best balance of improved performance without sacrificing too much driveability.
Finally, you must ensure compatibility. This seems obvious, but it is critical. Your new ACT flywheel must match your engine’s bolt pattern and your transmission’s input shaft. Check the specific model number for your vehicle’s make, model, year, and engine code. Also, remember that a flywheel replacement is almost always done alongside a clutch job. It is the perfect time to install a new clutch, pressure plate, and throw-out bearing. Do not reuse the old ones. Getting this right is the key to a successful upgrade, which is why reading a detailed 10 Best ACT Flywheel Reviews and Installation Guide can be so helpful before you buy.
FAQ
What is the main benefit of a lighter flywheel?
The main benefit is improved engine responsiveness. By reducing rotational mass, the engine does not have to work as hard to spin up. This means you will feel a quicker rev-up when you press the gas pedal. It can make the car feel more lively and accelerate faster, especially in the lower gears. The downside is that it can make the car slightly more difficult to drive smoothly in traffic, as the engine has less inherent momentum to keep it from stalling at very low RPMs.
Can I install an ACT flywheel myself?
You can, but I would only recommend it if you have significant mechanical experience and the right tools. The job requires safely supporting the vehicle, removing the transmission, and properly torquing the new flywheel to the engine’s crankshaft with a precise pattern. A mistake in installation can lead to serious damage or a vehicle that is unsafe to drive. For most people, paying a professional mechanic is the wiser and safer choice.
Do I need to resurface an ACT flywheel before installation?
No, you should not resurface a new ACT flywheel. They are manufactured to exact specifications and come with a surface finish that is ready for the clutch disc right out of the box. Resurfacing it could actually alter the critical height and step dimensions, leading to improper clutch engagement and premature wear. If you are reinstalling a used ACT flywheel, you should contact their technical support to see if it is a candidate for resurfacing.
What is the difference between a street and a race flywheel?
The difference typically comes down to weight and material. A street flywheel, like ACT’s Streetlite, is heavier to maintain driveability and smoothness for daily use. A race flywheel is often made from aluminum and is as light as possible to maximize engine response, sacrificing some low-speed smoothness. For a car that sees street and track time, a mid-weight steel flywheel is often the best compromise.
Is a lightweight flywheel bad for my engine?
A properly installed lightweight flywheel is not bad for your engine. It does change the driving dynamics, as I mentioned, but it does not cause harm. Some people worry about crankshaft stress, but for most street applications, the reduction in weight is well within the design limits of a healthy engine. The key is to pair it with a clutch that matches your engine’s torque output.
Where can I find a reliable installation guide?
The best resource is often a vehicle-specific forum or a detailed video tutorial for your car model. ACT also provides general installation guidelines. For a comprehensive look at options and the installation process, checking a dedicated resource like a 10 Best ACT Flywheel Reviews and Installation Guide can give you a great overview of what the job entails before you start. Always cross-reference multiple sources to be safe.