Spring Seat - Chromoly 1.350 x .575 .060 Thick

The Spring Seat - Chromoly 1.350 x .575 .060 Thick by PAC Racing Springs is a precision-engineered component designed for high-performance engine builders and street machine enthusiasts who demand reliability under extreme valve train stress. This chromoly steel seat functions as the critical interface between your valve spring and cylinder head, providing consistent load support across thousands of compression cycles. Whether you're building a naturally aspirated stroker or a forced-induction application, a quality spring seat directly impacts valvetrain stability and prevents seat migration—a common failure point in upgraded spring packages.

Machined from chromoly steel stock, this spring seat features a 1.350-inch outer diameter with a 0.575-inch bore, and a wall thickness of 0.060 inches—specifications that deliver optimal stiffness-to-weight ratio and superior load distribution. The chromoly material provides significantly greater fatigue resistance than mild steel alternatives, essential for sustained high-RPM operation and repeated thermal cycling. The precise dimensions ensure proper seating geometry that maintains coil bind clearance while maximizing spring preload consistency, directly affecting valve timing accuracy and combustion chamber efficiency.

This component is ideal for builders upgrading to beehive or dual-spring packages that demand increased seat pressure and dimensional precision. The compact 4.45 x 2.2 x 7.9-inch package weighing 0.705 lbs makes installation straightforward on most small-block and mid-block platforms. Verify bore diameter compatibility with your existing valve stem before purchase; proper seating eliminates noise, reduces valve float, and extends both spring and seat life in competition or street applications.