SBC Xtreme Hyd. Roller Cam XR300HR-10

The COMP Cams SBC Xtreme Hydraulic Roller Cam XR300HR-10 is a purpose-built camshaft engineered for small block Chevy engine builders seeking aggressive mid-range performance without sacrificing reliability. This hydraulic roller cam delivers 0.562-inch intake and 0.580-inch exhaust valve lift across a 300/306-degree duration window, tuned specifically for street and strip applications operating between 3200 and 6200 RPM. The 110-degree lobe separation angle balances drivability with noticeable power gains across the mid-range and top-end powerband.

Hydraulic roller technology provides reduced friction and wear compared to solid cam profiles while maintaining the aggressive lift characteristics necessary for serious performance. The XR300HR-10 specifications translate to improved cylinder filling and scavenging, resulting in measurable horsepower gains on both naturally aspirated and moderately boosted small block applications. This cam requires compatible roller lifters, a quality valve train, and proper carburetor or fuel injection tuning to achieve full potential. Installation demands precise timing verification and valve lash adjustment for optimal efficiency and longevity across sustained high-RPM operation.

This camshaft is ideal for small block Chevy enthusiasts building street rods, muscle car restorations, and weekend performance vehicles where reliable part-throttle manners matter as much as peak horsepower. The XR300HR-10 fits engines with standard small block Chevy bore diameters and stock deck heights. Builders integrating this cam into 350, 355, or 383 cubic-inch packages will experience noticeable improvements over stock profiles while maintaining compatibility with factory-style accessories and conventional cooling systems.