COMP Cams Camshaft CS XR300HR-10

This COMP Cams Xtreme Energy camshaft, part number 12-444-8, features a 248-degree intake and 254-degree exhaust duration with a .550-inch lift on both. It’s a hydraulic roller design specifically for Chevrolet Small Block Gen 1 engines, designed to bridge the gap between street cams and race-only components. This camshaft aims to give you a significant boost in torque, better throttle response, and increased vacuum compared to stock, all while maintaining the durability needed for daily driving and quiet valve train operation.

Built for Pro Street and bracket racing applications, this cam works well with a 10:1 compression ratio and a 3500+ RPM stall speed torque converter, paired with good intake and header setups. While it offers substantial performance gains, expect a notably rough idle due to its aggressive profile. It’s important to verify your engine’s setup; this camshaft is intended for blocks that use a flat tappet camshaft. GM gradually transitioned to roller camshafts starting in the mid-1980s, with some models like Camaros and Corvettes receiving them earlier than trucks and SUVs, which sometimes retained flat tappets into the mid-1990s. Removing the intake manifold or timing cover is the surest way to confirm if your block is factory roller-ready or requires a flat tappet camshaft.

This camshaft fits a wide range of Chevrolet Gen 1 Small Block engines, including popular displacements like the 350, 400, 327, and 283. It is compatible with many vehicles from the 1980s and early 1990s, such as the Chevrolet C10, Caprice, Camaro, and El Camino, as well as Buick Roadmaster and Cadillac Fleetwood models from that era. Please note that this camshaft is not compatible with LT1/LT4 engines or factory roller small blocks from 1985 and newer. For 1955-1957 Chevrolet 265 engines, ensure there is an oiling groove on the fifth cam journal.