Hays Street 650 single disc kits are designed to handle highly modified engines up to 650 naturally aspirated horsepower (600HP for forced induction & nitrous combinations). Designed as a true Street/Strip clutch for spirited high-performance driving or frequent track use. The high-performance disc utilized in the Street 650 has an 8-spring hub with encapsulated damper springs and a sintered metallic friction surface. The encapsulated spring can handle 3 times the shock load versus a standard coil spring. Sintered metallic material provides a degree of slippage on vehicle launches to prevent violent engagement characteristics found in paddle-style metallic discs. This kit includes a pressure plate, clutch disc, alignment tool, and instructions. *This clutch is made to work with the early flat style flywheels found on LS1 and LS6 engines. It will not work with the recessed surface flywheels found on LS2, LS3, and LS7 engines. **Pair with Hays 10-730 or 20-730 for a perfect match.