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Stacks of full face semi metallic friction material await riveting to discs. |
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Hubs ready to have friction material installed. You can use pucks or a full face on this hub assembly. |
The hub center is precision broached for a tight fit on the transmission’s input shaft splines. This is essential for long life and not having the splines pull out or wear the input shaft causing the clutch action to get sticky as the disc gets hung up on the wear areas.
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Pucks being riveted to the disc. |
After broaching, the hubs are assembled to the rest of the disk by riveting. ACT uses large head heavy duty rivets that are simultaneously pressed in large bespoke fixtures in huge multi ton hydraulic presses to ensure even and correct installation. Various types of friction material are riveted to the disc as well.
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Some discs use a press and this fixture to fix the rivets all at once. |
Solid hub metal puck discs use a puck holder that is designed with smooth curves to reduce stress risers that tend to make the arms crack and fail at their base when they are riveted to the hub. Weight is reduced with holes in the middle of the puck holder’s arms. ACT solid hub discs have twice the amount of rivets holding the hub center to the puck holder than their competition to reduce the chances of burst and failure considerably.
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ACT keeps plenty of stock in inventory. |
ACT makes many combinations of full face and puck discs with and without a smoothing marcel and hub springs in any number of combinations from fully streetable heavy duty single disc clutches to multi disc full race exotic clutches. With a complete product line up, excellent performance, high quality and a reasonable price, ACT is a company we will always consider when sourcing a clutch for our race and street projects.
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ACT, one of our preferred clutches. |
To learn how clutches work, you can read about it here!
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