Designed for extreme boost and high RPM racing engines. Made from ultra clean Silicon Chrome spring steel with a higher fatigue resistance compared to other spring steels. Heat treating and post processing is the highest quality available. High frequency spring design to reduce spring surge at high operating RPM. This kit is designed for the most powerful 1JZ engines on the planet.

• 130lb seat pressure at 34.60mm installed height.
• 250lbs at 11.0mm valve lift.
• Coil bind at 22.0mm.
• Extreme nose pressure, please use our KCF-229 DLC bucket for improved parts longevity.