Powergrip HD sets are the ultimate for extreme street/strip performance. Using proprietary 900 series friction material in conjunction with increased clamp load pressure plates, you get maximum holding power for track or street, with only minimal reduction in driveability. This is the set for big power street cars! Some chatter will occur on takeoff. Due to the 900 series disc in these kits we highly recommend the use of RAM billet steel Flywheel. Use of the factory nodular iron (explosion resistant) flywheels will cause excessive wear on the flywheel.