Adjusting Nut 1pk 7/16 x 2.600 BBC Intake

The AIR FLOW RESEARCH Adjusting Nut 1 Pack 7/16 x 2.600 BBC Intake (Part No. 6215-1) is a precision rocker arm nut engineered for big-block Chevy engine builds. This 7/16-20 thread fastener measures 2.600 inches in length and is manufactured from hardened steel with a black oxide finish, providing corrosion resistance and consistent clamping force across thermal cycling and high-RPM operation. Designed for use with stud girdle configurations, this adjusting nut ensures proper valve train geometry and secure preload on rocker arm assemblies.

The 7/16-20 thread pitch and 2.600-inch length are critical specifications for big-block Chevy applications, where precise rocker arm positioning directly impacts valve timing and lift characteristics. Black oxide coating protects against rust and galling while maintaining the bearing surface integrity required for smooth rocker arm pivot action. The steel construction handles the vibrational stresses of high-performance engines without deforming or loosening under load, critical for maintaining consistent valve events across extended drive cycles.

This single-piece nut is suited for engine builders, performance technicians, and enthusiasts rebuilding or upgrading big-block Chevy cylinder heads with aftermarket rocker arm systems. Whether assembling a street engine or a track-focused build, correct rocker arm preload is non-negotiable for valvetrain reliability. AIR FLOW RESEARCH components are industry-recognized for precision tolerances and fit, making this adjusting nut an OEM-quality replacement or upgrade component for BBC intake manifold and valve train assembly work.