Shim Kit - 1.250 Dia.

The Shim Kit - 1.250 Dia. from PAC Racing Springs is a precision valve spring shim set designed for engine builders and performance enthusiasts who require precise control over spring preload and seat pressure. This kit is essential for tuning street performance engines, preparing for road course competition, or optimizing high-revving rebuilds.

Manufactured to tight tolerances, these shims ensure that each disc sits flat and uniform under the spring seat, preventing bind or rocking. The 1.250-inch diameter is compatible with many domestic and import cylinder heads, and the hardened steel construction resists galling while maintaining dimensional stability across thermal cycles.

This shim kit is invaluable for those installing performance or oversized valve springs, swapping cam profiles, or rebuilding heads to exact OEM specifications. Proper shim selection is crucial to prevent valve float and ensure reliable engine performance.