SBC Pro-Mag Rocker Arm 1.52 Ratio 3/8 Stud

The COMP CAMS SBC Pro-Mag Rocker Arm 1.52 Ratio 3/8 Stud is a precision-engineered rocker arm assembly designed for serious small-block Chevy and GM V6 builders who demand reliable valve actuation and consistent lift across the rev range. Whether you're building a street engine, bracket racing platform, or performance cruiser, this full roller rocker delivers the durability and mechanical advantage needed to unlock your camshaft's true potential. Rocker arm ratio—the leverage multiplier between pushrod and valve stem—directly controls valve lift and duration at the valve, making component selection critical for engine performance and longevity.

Built from chromoly steel and featuring a full roller design, the COMP CAMS SBC Pro-Mag Rocker Arm minimizes friction losses and wear on the camshaft lobe and valve stem. The 1.52 ratio geometry amplifies pushrod motion by a factor of 1.52, translating to increased valve lift and improved cylinder head breathing—especially valuable when paired with aggressive cam profiles and high-flow heads. The 3/8-inch stud mount interface ensures rock-solid attachment to your small-block Chevy's cylinder head, while the roller design reduces parasitic drag and heat generation during sustained high-RPM operation, protecting both the valvetrain and your overall engine efficiency.

Mechanics and engine builders favor the SBC Pro-Mag Rocker Arm for any small-block Chevy or compatible GM V6 project where stock rocker geometry falls short of performance goals. This is the valve control component for 350, 383, 400-cubic-inch platforms and corresponding V6 applications running aftermarket cams, ported heads, and higher-lift profiles. Installation requires standard pushrod and rocker stud hardware; verify pushrod length and stud condition during assembly to ensure proper geometry and eliminate valve-to-piston clearance issues. Each rocker arm weighs 0.65 lbs and measures 2.8 x 2 x 4.1 inches, fitting seamlessly into standard small-block heads and complementing both stock and performance cylinder head designs.