1.250 O.D. Spring Shims .814 I.D. .030 Thickness

The 1.250 O.D. Spring Shims .814 I.D. .030 Thickness from COMP CAMS is a precision valvetrain component engineered for engine builders and performance enthusiasts who demand exact valve spring control. These shims sit beneath valve springs to adjust preload height and maintain critical spring pressure across the RPM band. Whether you're dialing in a stock rebuild, fine-tuning a modified cam package, or optimizing a high-performance engine, selecting the correct shim thickness is non-negotiable for reliability and power delivery.

Manufactured to tight tolerances by COMP CAMS—a trusted name in valvetrain engineering—each shim features a 1.250-inch outer diameter, .814-inch inner diameter, and .030-inch thickness that work in concert with your spring stack to achieve target installed height. The .030-inch profile allows for fine adjustment increments; stacking multiple shims lets you dial in exact preload without forcing new springs into service. Proper shim selection prevents valve float at peak RPM, reduces spring coil bind risk, and ensures consistent lift across your entire powerband. The precision-ground flat surfaces guarantee solid seating on the spring seat and retainer, eliminating rocking that causes accelerated wear.

These shims are essential when installing aggressive cam profiles, upgrading to stiffer springs, or correcting spring pressure on older engines where original shims have compressed. They work across virtually all small-block and big-block applications where .814-inch spring seat bores are standard. Verify your spring's installed height requirement and current shim stack before ordering; incorrect preload destroys lobes and rocker arms. COMP CAMS shims deliver the OEM-quality consistency that separates a weekend rebuild from a engine that runs 50,000 miles trouble-free.