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

The COMP CAMS BBC Ultra Pro Magnum XD Rocker Arms 1.8 7/16 are designed specifically for big-block Chevrolet engines that require maximum valve lift and reliable high-RPM performance. These rocker arms are ideal for serious enthusiasts who are building BBC-powered street machines, race cars, and high-performance trucks where standard components may not suffice.

Featuring a 1.8 ratio and a 7/16-inch pushrod diameter, the Ultra Pro Magnum XD design incorporates needle roller bearings to reduce friction and hardened steel construction to withstand extreme valve spring pressures. This mechanical advantage enhances cam lift across the RPM range, resulting in improved valve opening velocity and airflow compared to lower ratio alternatives. The precision-ground fulcrum points and optimized bearing clearances further minimize parasitic drag, allowing for more horsepower to reach the wheels.

These rocker arms are particularly beneficial for both naturally aspirated and forced-induction BBC builds, ranging from 427 street engines to full-race 496-cube competition motors. Installation requires compatible BBC cylinder heads, adjustable pushrods, and verification of valvetrain geometry, especially concerning pushrod length. This ensures optimal performance and longevity for your engine setup.