Stud Girdles Adj Nut 1pk 3/8 SBC/SBF

The Stud Girdles Adj Nut 1pk 3/8 SBC/SBF from Air Flow Research is a precision rocker arm nut engineered for small-block Chevrolet and Ford V8 engines. This component serves as a critical fastener in the rocker arm assembly, securing the rocker arm to the cylinder head stud while maintaining proper geometry under valve train loads. Engine builders, performance technicians, and Chevy V8 enthusiasts rely on quality stud girdle nuts to ensure reliable valve operation and prevent rocker arm movement during high-RPM operation.

This adjustable nut features a 3/8-24 thread specification, matching OEM and aftermarket stud girdle systems on small-block Chevrolet and Ford platforms. Constructed from steel and finished in black oxide, the nut resists corrosion and provides excellent durability in high-temperature engine compartments. The black oxide coating enhances appearance while offering modest wear resistance, and the adjustable design allows technicians to fine-tune rocker arm preload and geometry during valve train setup—a critical step in optimizing valve timing, lift accuracy, and overall engine performance.

This single-pack nut is ideal for engine builders assembling or rebuilding small-block V8s, particularly those using stud girdle rocker arm systems on SBC (small-block Chevy) or SBF (small-block Ford) platforms. Proper installation with correct preload ensures consistent rocker arm lift and prevents valve train noise or component failure under load. Whether replacing worn fasteners, building a performance engine, or upgrading a stock valve train, this Air Flow Research component delivers the precision fit and finish expected by serious engine builders.