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3/8 Rocker Arm Nut Polylock NB SA – 1

Product Information
Part Number: PL38SA-1
Our Price: $5.99
Engine Type
Engine Family
Mounting Style
Stud Size


Polylock Self Aligning & Narrow Body – Scorpion Racing Products 3/8 Self Aligning & Narrow Body Polylock – Rocker Arm Nut

  • High performance, hardened steel
  • Made from 4140 machined steel with a black oxide coating for surface protection
  • Overall Length 1.030″
  • Outside Diameter .525″
  • Single piece

Scorpion Racing Products 3/8" Self-Aligning Polylock

Made in the USA! That says it all!

A Polylock is an adjustable rocker arm nut. They are used with Stud Mount Rocker Arms.

How do they work?

A polylock features a threaded body and a set screw.

An Example of a Polylock

The body screws over the stud and holds the rocker arm in place. Then, the set screw is tightened down against the stud. This locks the body in place.

Why would I need them?

Polylocks make adjusting you valvetrain much easier. They are useful when Setting Preload on hydraulic lifters. They are required to Set Valve Lash on solid lifters.

Polylocks also come in various lengths. The longer body sticks up above the rockers to attach a Stud Girdle

Watch as Scorpion’s Design Engineer shows you how to set valve lash.

Additional information

Weight 0.052 oz
Dimensions 2 × 3 × 1 in


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