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Dual Valve Spring & Titanium Retainer Kit

Supertech valve spring kits are engineered for accurate high rpm valve actuation with more aggressive cam profiles. Dual springs reduce stresses and valvetrain harmonics that can adversely affect durability. Springs are manufactured from superclean chrome silicon vandaium steel and are gas nitrided prior to shot peening to improve fatigue life. Each kit includes a full set of springs, hardened spring seats, and lightweight titanium retainers.

Usually ships in 2 to 3 days.

Manufacturer: Supertech

Applications:

  • Subaru EJ205/EJ207
  • Subaru EJ255/EJ257

What is the importance of the valve spring? The role of the valve spring is to ensure that the valve movement accurately follows the camshaft lobe. Valve float occurs when the valve spring is unable to control the inertia of the valvetrain and the valve and lifter lose contact with the cam lobe. Therefore the spring requirements are dependent on the masses of the valvetrain components in motion and the engine speed as well as the agressiveness of the cam lobe profile. Ideally the minimum spring force necessary to achieve accurate valve movement at the desired maximum rpm should be used because otherwise you are adding undesirable friction and component stresses.

What is the advantage of a dual valve arrangement? This arrangement allows for the use of thinner spring wire so that greater valve lifts can be used without coil bind. Additionally, most have an inner spring with a slight interference fit with the outer spring. This adds a level of damping to the valve spring harmonics to allow for higher rpm operation and longer life.

What is a beehive spring? A beehive spring has a small diameter top coil which reduces spring and retainer inertia. The variation in coil diameters and spacing significantly reduces valve spring harmonics.