The Five Stages Of SPEC Performance Clutches

No matter the environment or the application, SPEC Clutches, among the leading manufacturers of high performance aftermarket and racing clutches and driveline accessories, has an answer for it.

SPEC offers five distinct stages of performance clutches in their product catalog, each with their own driving and use conditions, power ratings, torque capacities, and features. Within these five stages, seven different performance clutches are offered.

The Stage 2 clutch, featuring a segmented or full-faced pure Kevlar disc with steel backing and offers slightly longer life and higher torque capacity than the Stage 1.

The Stage 1 clutch, intended for street, drag racing, drift, road racing, rally, pulling, and autocross use, features an integrally molded carbon kevlar-based, high performance organic lining offering smooth engagement and excellent life. Among the features are a high clamp pressure plate, steel-backed and multi-compound woven organic material, high torque sprung hub and disc assembly, and a bearing and tool kit.

Stage 2, for street, drag racing, pulling, and autocross use, features a segmented or full-faced pure Kevlar disc with steel backing and offers slightly longer life and higher torque capacity than the Stage 1. The Stage 2+, meanwhile, bridges the gap between the Stage 2 and 3 with the drivability and engagement quality characteristics of the Stage 2 with 15-20% higher torque capacity.

Stage 3, with the same applications as the Stage 2, features a carbon semi-metallic six-puck sprung hub disc that is the leading puck clutch in drivability, life, and torque capacity. It’s designed for street and race cars with aggressive but street-able engagement and high torque capacity. The Stage 3 is available with a three puck configuration.

SPEC's Stage 3 clutch assembly.

The similar Stage 3+, for high powered street and race cars requiring a manageable and friendly engagement, this clutch offers carbon semi-metallic full faced material with exceptional life, friction co-efficient, and drivability characteristics in a single package.

Stepping up a bit more, the Stage 4 unit is a solid hub version of the Stage 3. It features a solid 8-rivet hub and a heat treated assembly for strength and durability and is available in 3, 4, or 6 puck configurations. The 3 puck offers the lightest, the 6 puck the smoothest engagement, and the 4 nestles in as the compromise of both. The Stage 4 is an exceptional choice for street cars, drag racing, pulling, and autocross.

Last but certainly not least, the Stage 5 performance clutch brings full metallic discs to the table with the highest possible friction coefficent. This clutch setup is street drivable but not exactly street friendly – making it great for all-out performance drag racing, pulling, and autocross use. The Stage 5 features a solid 12-rivet hub with a heat treated assembly. Extreme street cars and drag racing are the best applications for such a clutch system.

To learn more about these and other clutch systems and accessories from SPEC Clutches, log on to

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About the author

Andrew Wolf

Andrew has been involved in motorsports from a very young age. Over the years, he has photographed several major auto racing events, sports, news journalism, portraiture, and everything in between. After working with the Power Automedia staff for some time on a freelance basis, Andrew joined the team in 2010.
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