Competition Clutch Clutch Flywheel

Competition Clutch Flywheels: Engineered for Rotating Mass Reduction

When it comes to performance flywheels built specifically for sport compact enthusiasts, Competition Clutch has established a reputation that spans track days, drag strips, and spirited street drives alike. Clutch flywheels are a critical link in the drivetrain — they store rotational energy, smooth power delivery, and directly influence how quickly an engine revs. Swapping a heavy OEM unit for a well-engineered lightweight flywheel can transform throttle response and make the entire powertrain feel more alive.

The ST and STU Flywheel Lines

Competition Clutch offers two primary flywheel variants to match different build goals. Lightweight Steel Flywheels (ST suffix) are recommended for naturally aspirated and street-driven applications, preserving low-end torque and driveability. For more aggressive setups, the Ultra-Lightweight Steel Flywheels (STU suffix) push weight reduction even further — reducing mass to increase acceleration at the cost of some low-rpm smoothness, making them ideal for track-focused or Stage 3+ clutch pairings. Flywheel weights vary from 8 lbs to 18 lbs depending on application.

One-Piece 4140 Forged Steel Construction

Competition Clutch flywheels are made of 4140 forged steel and feature a one-piece design, which helps significantly reduce the chances of ring gear separation and friction surface warpage. This matters because many OEM flywheels use a two-piece construction where the ring gear is a press-fit component — a known failure point under performance use. Built from one-piece 4140 forged steel and CNC-machined to OE specifications, these flywheels handle high-heat track sessions and the Blanchard-ground friction surface provides consistent clutch engagement from cold start to hot laps.

Broad Compatibility Across Sport Compact Platforms

These flywheels will work with all performance and stock clutch assemblies, making them a versatile upgrade whether you are running a stock pressure plate or a full multi-stage Competition Clutch kit. Coverage spans a wide range of popular sport compact platforms — Honda B-Series, K-Series, Subaru EJ and FA engines, Mitsubishi 4B11, and more. Competition Clutch also produces lightweight flywheels sold separately or integrated into kits, with an extensive choice of models designed for a very large number of American, Japanese, and European cars.

Heat Management and Resurfaceability

One overlooked advantage of the forged steel approach is thermal behavior. Forged steel soaks and sheds heat better than aluminum and gives a more predictable pedal feel when things get hot — that's why turbo builds, road-race cars, and endurance setups lean toward 4140 forged steel flywheels instead of the lightest possible unit. Additionally, these flywheels can be resurfaced like an OEM flywheel when it's time for a clutch replacement, rather than being thrown away, saving money over the long run.

Proven in Competition

Since 2003, Competition Clutch has been manufacturing high-performance transmission products known for their solid build and very competitive prices, and their flywheels have been a core part of that lineup from the start. Specializing in manufacturing sport compact assemblies from street-driven to full race applications, Competition Clutch products are proudly used in some of the fastest sport compact race cars in the country. Whether you are building a weekend track car or tuning a daily driver for more engagement, a Competition Clutch flywheel represents a well-tested, cost-effective upgrade.