Ferrea Racing

Ferrea Dual Valve Spring Kit | Multiple 4G63T Fitments (SL1009)

  • Sale
  • $746.56
  • Regular price $1,037.44

Harmonics or high frequency fatigue is present in all racing engines and will usually destroy the valvetrain if not controlled. Properly designed valve springs will control the dominant harmonics, provide the needed stability, and reduce valvetrain component wear.

Ferrea valve springs are developed from high strength alloys, including premium grade chrome silicone steel. These springs are manufactured with state-of-the-art equipment. Our springs are heat-treated and stress-relieved, which dramatically increases the spring's life. Strict quality control procedures and cycle testing ensures consistency from batch to batch. Ferrea valve springs provide the stability needed for high lift, high rpm racing engines, while minimizing the load loss for today's aggressive valvetrain combinations.


  • Developed from high strength alloys
  • Springs are heat-treated and stress-relieved
  • Manufactured with state-of-the-art equipment


  • Dramatically increases the spring life
  • Provide the needed stability for high lift, while minimizing the load loss
  • Reduce valvetrain component wear

Seat Pressures:

  • Standard Pressure (Special Alloy): 80 lbs @ 34 mm
  • High Pressure (Chrome Silicon): 90 lbs @ 38 mm


  • 2003-2006 Mitsubishi Lancer Evo 8 & 9

What's in the box?

  • 16 dual valve springs
  • 16 titanium retainers
  • 16 seat locators