4212210 is a 4-pad spring-centered race disc made with high quality, ceramic friction materials. The engagement is harsher, but shifting is faster. The heavy duty torsional dampening springs are stronger, in most cases, than standard springs and are provided in the best sizes and spring rates to suit the application. The race disc features a heat-treated spring steel drive plate and is well-suited for the smaller disc sizes in smaller engines.
Aggressive engagement, quick shifts, OE to mild gear rattle
Premium ceramic friction materials provide moderate wear rates and high heat tolerance
Utilizes wraparound spring windows, thicker retainer stampings and a heat-treated, spring steel drive plate to provide support, reduce stress concentrations and increase strength and reliability
Recommended for race use only
High burst strength and holds 28% more torque than typical organic materials
Can an ACT Race puck-style disc be used for daily driving, and is it recommended?
ACT's race discs are very aggressive and provide no-nonsense performance response. As a result, the engagement is harsh. Taking off from a stop can cause judder and/or an uncomfortable noise. These characteristics
have no effect on the performance on the clutch or the drive line components. This type of disc should only be used in a professional race setting and never on the street. ACT always recommends using an organic disc
on the street because it offers a smoother engagement and a longer lasting performance value for everyday drivers.
When should a clutch disc be replaced?
The majority of new discs measure .312-.315” (7.93 – 8.00mm) thick – fully worn is .275” (7.00mm) or below. A few applications (mostly Audi and BMW) start out at .332 - .335” (8.43 – 8.50mm). These are to be replaced
when below .295” (7.50mm). It’s best to measure with a micrometer. Puck discs are measured as-is, where organic street discs are correctly measured by fully compressing the engagement cushion (marcel) between the
linings. If the lining rivets on either side of the disc have made contact with the flywheel or pressure plate face, the disc must be replaced. Note: Using a disc that is thicker or thinner than the working range the
pressure plate is designed for will have varying, and often very poor, results.