EXEDY: The Japanese Giant Transferring Power to the Ground
In the world of drivetrains, there are clutches, and then there is EXEDY. Founded in Japan in 1950 as Daikin Manufacturing, this company is now the largest OEM clutch supplier for the Japanese automotive industry. From Kei cars to the Nissan GT-R, there is a high probability that your Japanese car came with an Exedy clutch from the factory. But the brand's true fame comes from its Exedy Racing Clutch division.
ATOMIC-SHOP is an official Exedy dealer. We offer the full spectrum of solutions: from reinforced organic kits for street tuning to carbon multi-plate systems for professional drag racing and drifting. Exedy is the choice for those who want every kilowatt of engine power to reach the wheels, rather than turning into smoke and the smell of burnt linings.
Organic or Ceramic? Choosing Stage 1 vs. Stage 2
This is the most common question for builds up to 400-500 HP. Exedy offers two distinct paths:
Stage 1 (S-Type / Organic)
The ideal choice for "Street" cars.
Disc: Uses Ultra Fiber friction material—an organic compound woven with copper wire and high-strength glass fiber. This ensures high heat resistance (won't fade in traffic) while maintaining the soft pedal feel and smooth engagement of a stock clutch.
Cover: Reinforced, with higher Clamp Load (typically 40% stronger than stock).
Stage 2 (Cerametallic)
The choice for track days, rallying, and drift.
Disc: Cerametallic (Sintered Iron). Features a paddle design (3 or 4 pucks).
Behavior: Ceramic has a higher friction coefficient and withstands extreme heat. However, engagement is abrupt (On/Off). Smooth starts are difficult, and "chatter" (judder) is common. This is the trade-off for racing reliability.
Hyper Series: The Legendary Purple Cover
When power exceeds 500-600 HP, a single-disc clutch is often insufficient. Enter the Hyper Series (Hyper Single, Hyper Multi). These are complete kits including a lightweight flywheel, disc(s), and cover.
| Model | Construction | Features |
|---|---|---|
| Hyper Single | 1 Disc (Cerametallic). | Compact module. Forged aluminum cover (extremely stiff). Holds 400-500 Nm. Perfect throttle response. |
| Hyper Multi (Twin/Triple) | 2 or 3 Discs (Cerametallic). | Friction area doubled or tripled. Holds 800-1200+ Nm of torque. The choice for D1GP and Time Attack. |
| Carbon-D / Carbon-R | Carbon Fiber Discs. | The pinnacle of technology. Lightest weight, smoothest engagement, incredibly heat resistant. |
Carbon: Why is it the Holy Grail?
Many think carbon clutches are only for pros. In reality, they are the best clutch for a high-power street car.
The secret lies in carbon physics:
1. Weight: A carbon disc weighs 3-4 times less than steel. This allows for lightning-fast shifts as the transmission synchros have less mass to stop.
2. Thermal Coefficient: Standard ceramic can fade when hot. Carbon increases its friction coefficient as it gets hotter. The hotter it gets, the better it grips.
3. Smoothness: Carbon has a unique ability to slip (half-clutch) without destroying itself. This allows for smooth starts in traffic, even in a 1000 HP GT-R.
Dampers: Fighting Vibration
Exedy clutches are known for their advanced dampers (springs in the disc hub). The WAD (Wide Angle Damper) technology absorbs engine torsional vibrations and protects the drivetrain from shock loads during harsh launches.
Exedy also patented the "Quiet Strap Drive" for multi-plate clutches. This strap system holds the floating plates in place, preventing the annoying "rattle" noise when the clutch pedal is depressed, making the Hyper Series significantly quieter than competitors.
Frequently Asked Questions (FAQ)
Why does a twin-plate clutch "rattle"?
In multi-plate systems, there are intermediate steel plates (floaters). When you press the clutch pedal, the plates separate and float freely. Engine vibrations cause them to knock against each other, creating a characteristic metallic ringing sound. This is completely normal for a racing clutch and is not a defect.
Is a break-in period required?
Yes! For Organic (Stage 1) clutches, about 500-800 km of city driving is needed. For Cerametallic and Carbon, the break-in process is faster but still essential to mate the surfaces and ensure 100% contact area before the first full-throttle launch.
What is SMF Conversion?
Many modern cars have a Dual Mass Flywheel (DMF), which dampens vibration but is unreliable and heavy. Exedy Hyper Series kits are SMF Conversions (Single Mass Flywheel). They replace the heavy DMF with a lightweight solid flywheel. This makes the engine much more responsive but may introduce some gear rollover noise at idle.
Put all your power to the pavement. Choose EXEDY clutches at ATOMIC-SHOP — an official partner of the Japanese legend.