Cosworth High Performance Valvetrain - Ultra Race Valve Spring Kits for Subaru Impreza WRX STI Limited 2004-2008

Cosworth Ultra Race Valve Spring Kits engineered use in situations that require valve control in extreme condits. Each consists of dual valve springs with matched lightweight titanium retainers; keepers; hardened steel springs seats. Cosworth Ultra Race Valve Springs wound from highest quality chrome silicone steel with chamfered ends are heat treated stress relieved long term reliability. Ultra Race Valve Spring kits compatible with Cosworth high performance valves.