ARP Perma-Loc Rocker Arm Adjusters Chrome Moly

ARP Perma-Loc rocker arm adjusters, also sold as rocker arm adjusting nuts or poly locks, are made for engines that need to hold their valve lash setting. The patented design is meant to stay put, so you don't have to keep re-tightening the adjusters.

Key Features:

• Premium material: Forged from heat-treated 8740 chrome moly alloy steel with 190,000 psi tensile strength.
• Through-hardened body: The body is heat-treated all the way through, not just case hardened. This reduces the thread movement common to other adjusters.
• Precision-machined threads: The threads are cut exactly perpendicular to the base. The adjuster seats evenly and applies pressure around a full 360° circle.
• Flush-ground set screw: The locking set screw is machined flat on the bottom, not pointed. This gives better contact with the rocker arm stud.
• 12-point head: The compact head holds your wrench in place while you lock the set screw with an Allen wrench.
• Easy installation: No special adjusting tools are required.

The Perma-Loc line is available in several configurations to suit different rocker arm styles. ARP builds these adjusters for high-performance and racing valvetrains that need a lasting valve lash adjustment.