Isky Racing Cams 9975 Tool Room Dual Valve Springs 1.560" O.D.

The Isky Racing Cams 9975 Tool Room valve springs represent the pinnacle of racing valve spring engineering, designed for serious performance enthusiasts who demand uncompromising reliability at high RPM. Part of Isky's legendary 9900 Series "Gold Stripe" Tool Room line, these springs are the world's only endurance test-certified racing valve springs, earning the distinction of being "One of the Thousand" - alumni of the grueling 1,000-mile Spintron endurance test.

Key Features:

• Dual spring design with integrated damper for superior harmonic control
• 1.560" outer diameter with 0.740" inner diameter configuration
• 245 lbs seat pressure at 1.970" installed height
• 585 lbs open pressure at 1.290" valve lift
• 1.190" coil bind height for precise valvetrain geometry
• 480 lbs/in spring rate for consistent performance
• Manufactured from high-alloy steel with precision CNC machining

Every batch of Tool Room springs undergoes two complete 1,000-mile Spintron endurance tests with zero failure tolerance. No breakage and no excessive load loss are permitted - it's pass or fail. This rigorous testing ensures that only the strongest, most reliable springs make it into your engine, providing sustained redline protection when you need it most.

These Tool Room valve springs are ideal for high-performance street engines, drag racing applications, and competition builds requiring dependable valvetrain control at elevated RPM ranges. The dual spring design with damper effectively eliminates harmful resonant vibration that can cause ordinary valve springs to fail during sustained high-RPM operation.

When engine performance and reliability are non-negotiable, Isky Tool Room valve springs deliver the proven durability that has made the Isky name legendary in racing circles worldwide.