EXEDY Clutch

Who is Exedy?

EXEDY Globalparts Corporation (USA) is a wholly owned subsidiary of the EXEDY Corporation of Japan. EXEDY (Japan) was founded in 1923 and its clutch manufacturing business and prominent brand name Daikin Clutch are known throughout the world for supplying quality powertrain products.

The advanced engineering and patented innovations by EXEDY have made them a leading OEM manufacturer in the world for Clutches and other powertrain components.

In this article we will cover their Clutches. But first let’s go over the purpose of a clutch.

What does a Clutch Do?

A clutch disc is part of your vehicles manual transmission system. It’s responsible for delivering power from your engine to the transmission.  It is a steel plate covered in friction material and goes in-between your flywheel and the pressure plate.   In the center of your clutch disc is a hub that is splined to fit the transmission shaft.   When the clutch is engaged, the disc is pressed between the pressure plate and the flywheel.  Thereon, the power from the engine is transmitted through the hub and into your transmission. When your clutch is failing it will begin to slip against the flywheel. This will not allow your power to properly transfer from the engine to your transmission.

EXEDY Clutches

Stage 1 Organic

EXEDY Stage 1 Organic Racing clutch drivability is similar to the stock clutch. They feature an increased clamp load that gives the necessary capacity to handle modified engines. The higher clamp loads will also result in slightly higher pedal efforts.  The Stage 1 clutch discs by EXEDY has spring center dampers to reduce drivetrain shock and provide smooth clutch engagement.

Additionally, their Stage 1 clutch only uses premium friction materials. It’s developed by reviewing both the copper wire ratio and the composition of the high strength fiber. The Ultra Fiber Disc maintains the superior half-engagement feeling specific to the Organic material.  These materials are resistant to slippage and burst. The advanced facing material provides high heat resistance which is essential for enthusiast.

This is the ideal clutch for street and mild racing applications.

Stage 2 Cerametallic

Stage 2 Cerametallic Clutch by EXEDY
Stage 2 Cerametallic Clutch by EXEDY

The Stage 2 cerametallic clutches are able to handle much more abuse than a stock type disc without slipping and fading. They are designed specifically to handle the abuse of high power modified engines.

There are two types of cerametallic disc; thick and thin.

A thick disc has better heat capacity therefor has features durability under extreme conditions. A thin disc offers greatly reduced inertia to improve shift effort.  This allows for quicker shifting, and improved synchro durability. A thin disc is approximately ½ the thickness of a stick disc and is recommended for circuit track use only.

The Cushion Button Disc combines cerametallic button facing with marcel cushion springs to maintain comfortable driving while supporting a respectable amount of power. It’s smooth engagement is ideal for the street. Additionally, it can handle the power of high torque motors thanks to its heavy duty sprung hub dampening assembly. The Cushion Button Disc is currently available for limited applications, however more fitments will be released.

No matter what Exedy Stage 2 clutch disc you decide on, they all feature sprung center dampers to reduce impact and shock loads through the drivetrain.

Hyper Single Series

Hyper Single Series by EXEDY
Hyper Single Series by EXEDY

The Exedy Hyper Single Series clutch is designed to optimize the performance of moderately modified vehicles, but do not need the clutch capacity of a multi-plate clutch. This clutch is similar to EXEDY multi-plate clutches, featuring the same purple anodized forged aluminum cover. This cover is stiffer than a stamped cover and allows a higher lever ratio to main the pedal efforts at a reasonable level. In comparison to a pressed metal cover, this one has no clamp load deflection. Furthermore, the pressure plate features a series of turbine-like, air flow enhancing vanes. This keeps the clutch cooler under extreme operating conditions to improve wear life.

The EXEDY hyper series single clutch come with a chromoly steel flywheel and are normally supplied with a 6-puck cerametallic facing and a spring center damper disc assembly. The chromoly flywheel is lighter than the OEM which allows for an improved engine response and lighter assembly. It is also smaller and thinner than the OEM disc which allows for lower inertia. Lower inertia allows for quicker, easier shifting and less wear and tear on the transmission synchros.  The higher clamp load and cerametallic friction facings give approximately twice the holding torque of the OEM clutch and higher than other single disc clutches.

However, on select vehicles, the new VF (Various Friction) disc may be offered. The VF enables you to operate the clutch through an easy-to-feel half engagement thanks to the Ultra Fiber friction material.  The Ultra Fiber friction material also has a high heat dissipation and torque capacity due to the integrated metal facing.

Hyper Multi Series

Hyper Multi Series Clutch by EXEDY
Hyper Multi Series Clutch by EXEDY

The EXEDY Hyper Multi Series is designed for high-powered applications. It is specifically designed for high power street application, as well as drag, road and rally racing.  It is offered in twin and triple Multi-Plate clutches. The twin plate clutches are rated for approximately 500 ft/lbs of torque. Twins come with both spring damper discs or solid discs depending on application. The triple plates are rated for approximately 800 ft/lbs of torque. Triples are all solid discs and not recommended for street use.

The Hyper Muli-Plate clutch comes with a lightweight, chromoly steel flywheel and the famous purple anodized forged aluminum clutch cover. Additionally, they all have T5001 cerametallic friction materials for extreme heat resistance.

Most multi-plate clutches exhibit light pedal pressure thanks to a half-engaged “zone” provided by the patented clutch “cushion” function.

Hyper Compe Series

Hyper Compe Series by EXEDY
Hyper Compe Series by EXEDY

This clutch an ultralight metal mutli-plate clutch that is designed with a focus on racing.

It features exceptionally fast shifting and the lowest possible weight. When browsing this series you will see it its available in both Compe-R and Compe-D.

Compe-R will be the absolute lightest setup available. It utilizes 6 puck, 180mm or 200mm rigid discs. This clutch is ideal for time attack and Gymkhana, where fast shifting is desired over streetability. The Compe-D is an updated version of the Compe-R. It uses a high-capacity damper disc that protects the drivetrain from damage. It is an ultralight metal twin model with damper discs developed for frequent drift and circuit driving. Additionally, it can handle limited street use. Both come equipped with a lightweight forged aluminum clutch cover and ultra-light drilled chromium-molydenum flywheel, which provide the the lightest possible setup.

Hyper Carbon Series

Hyper Carbon Series by EXEDY
Hyper Carbon Series by EXEDY

The Hyper Carbon Series is the flagship model of EXEDY Clutches. These clutches are lightweight, durable, and resilient to high heat. The carbon disc are able to perform through long durations of high rotational velocity due to their precise application of carbon. The fibers are set one-by-one in a weaving pattern and baked at more than 3600°F, finalizing the strengthening process. The heat expansion rate is 1/20th of iron therefore eliminating a change in clutch feel that may happen due to distortion caused by expansion during driving. Carbon material also possesses a “non-stick” characteristic that eliminates disengagement problems.  Lastly, the carbon clutch is incredibly lightweight. It is one third that of a metallic disc.

Since this clutch utilizes a high friction coefficient Hyper Carbon disc it allows for quicker shift response. Low inertia discs allow the transmission to synchronize in a shorter space of time eliminating time loss during shift changing while also reducing the applied load to the synchronizer.

This clutch is available in single, twin and triple designs with both rigid or damper discs for a full range of power holding capacity.

Hyper Builder Series

Hyper Builder Series by EXEDY
Hyper Builder Series by EXEDY

Last but not least, The EXEDY Hyper builder Series. This clutch allows racers or custom car builders to assemble a clutch kit to fit their specific needs. This kit is similar to the Hyper Multi-Plate kit but does not include a flywheel. The builder kit can be used with any available flywheel, or custom made flywheels to match an EXEDY kit to virtually any transmission.

All EXEDY Hyper Builder Series kits come with HD clamp load and push type diaphragm for use with a 44-54mm release bearing. The lightweight cerametallic clutch discs are all 200mm diameter with solid hub for reduced mass and high torque holding capacities. Lastly, the clamp load on every kit is a pedal friendly 2653, which holds 615 torque on twin setups and 923 torque on Triples.

When opting to go with this series it is always recommended to speak to your builder. That way you can ensure you are getting the proper components for your vehicle.

In Conclusion

EXEDY pursuit of perfection and the assurance of safety underlie EXEDY famed quality and reliability. Quality and reliability are key when building your vehicle. You shouldn’t have to worry when hitting the streets, or on race day. With an EXEDY clutch you can lay power, without worry!