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Valve Spring and Retainer Set

GSC beehive valve springs and titanium retainers allow for more precise valve control and higher revs. The beehive spring design utilizes an ovate wire with advanced heat treatment for longevity and better stress distribution for reliability at high revs. With its narrowed top diameter it allows for a smaller and lighter spring retainer while at the same time providing a variable frequency which allows for higher rpms when compared to traditional springs. Nano-peened for durability.

Available either with titanium retainers or for use with stock retainers. Suggested max rpm and boost for GSC-5040 S2 (with S2 profile cam) 8500rpm/30psi and for S3 (with S3 profile cam) 10500rpm/44psi. For GSC-5039 S2 (with S2 profile cam) suggested max is 8200rpm/25psi (max valve lift is 11.2mm at valve).

Usually ships in 2 to 3 days.

Manufacturer: GSC Power-Division

Applications:

  • Mitsubishi EVO 4-9

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.