Machined from 8650 steel with a billet pushrod seat insert, these Ultra Pro Magnum XD rockers can handle up to 1,000 lbs of spring pressure. This 1820 rocker features a 1.7 ratio for use with 7/16" stud Chevrolet 396-454 Big Block.
For Big Block Chevrolet applications, 1.7 ratio, 7/16" stud; Machined billet pushrod seat insert; 8650 steel construction outlasts and outperforms other rockers in accuracy and strength; Ultra Pro Magnum XD Rocker Arm bodies are guaranteed against breakage for life;
