Spring Shims - 1.500 OD .030 Think

PAC Racing Springs Spring Shims — 1.500 OD 0.030 Thick — are precision valve spring shims engineered for high-performance engine builds where exact spring load tuning is critical. These hardened steel shims allow builders to dial in valve spring pressure with precision-matched thickness, ensuring optimal valve control across the RPM range without compromising seat contact or lifter geometry.

Each shim in this set of 16 measures 1.500 inches in outer diameter with a 0.570-inch inner diameter and 0.030-inch thickness. The 0.030-inch profile allows for fine load adjustments—stacking multiple shims provides cumulative spring rate correction for engines where stock springs fall short of target specifications. Steel construction resists deformation under sustained pressure, maintaining dimensional stability through thousands of heat cycles on both naturally aspirated and forced-induction platforms.

These shims are essential for high-revving applications—drag racing, road course competition, and street performance builds where aggressive cam profiles demand elevated spring pressure. Set quantity of 16 provides coverage for eight-cylinder engines with pairs per cylinder, or flexible configuration for smaller displacement engines. Serious builders rely on PAC Racing Springs shims for repeatable results across multiple engine builds.

Valve spring shimming is a foundational tuning step—incorrect spring load causes valve float at high RPM, loss of horsepower, and potential internal damage. These precision shims eliminate guesswork and allow exact specification compliance during engine assembly.