BBC Ultra Pro Magnum XD R/A's - 1.8 7/16

The COMP CAMS BBC Ultra Pro Magnum XD Rocker Arms with 1.8 ratio and 7/16-inch stud mount represent a premium upgrade for big block Chevy engine builds requiring maximum valve lift and precise control. These full roller rocker arms deliver the reliability and geometry necessary for high-performance applications where conventional stamped steel rockers fall short. Designed specifically for chromoly construction and engineered to withstand the demands of racing, street performance, and serious engine modifications, this 16-piece set supplies a complete rocker arm solution for dual quad or fuel injection big block platforms.

The 1.8 mechanical advantage ratio provides significant valve lift multiplication compared to stock geometry, enabling deeper valve opening for improved cylinder head flow characteristics and combustion efficiency. Full roller design minimizes friction and wear on both the pushrod and valve stem, extending component life and reducing parasitic losses during each valve cycle. The 7/16-inch stud mount pattern ensures direct compatibility with large-displacement big block Chevy heads while maintaining the rigid, vibration-free mounting required at higher RPM ranges. Chromoly steel construction offers superior fatigue resistance compared to cast iron, critical for sustained performance in turbocharged or supercharged applications.

This rocker arm set suits engine builders, performance shops, and enthusiasts executing comprehensive big block Chevy builds targeting increased horsepower and torque output. Applications include street performance vehicles, drag racing platforms, off-road competition, and marine installations where big block displacement and valve control demand professional-grade hardware. The Ultra Pro Magnum XD designation identifies this as COMP CAMS' high-end rocker arm platform, positioned for builders who refuse compromise on valvetrain stability and repeatability across wide RPM windows.