COMP Cams Camshaft CB XM 308HR-12

COMP Cams has a long history of building serious performance parts for race cars and street machines. This Xtreme Marine hydraulic roller camshaft, part number CB XM 308HR-12XM, is designed for Chevrolet Big Block engines like the 396 and 454. It’s a hydraulic roller design, which generally offers better performance and durability than flat tappet cams, especially in high-performance applications. This cam is particularly well-suited for jet boats with B impellers, especially when running a 10:1 or higher compression ratio, and is also a solid option for river drags or bracket racing where consistent power delivery is key.

The specifications for this camshaft are 254 degrees of intake duration and 260 degrees of exhaust duration at .050 inch lift, with a lobe separation angle of 112 degrees. This profile is optimized for engines with 10:1 or higher compression. It’s important to note that this camshaft is designed for use with a Melanized or Nitrided distributor gear. Using a cast iron or steel gear without these surface treatments will void the warranty and can lead to premature wear. This camshaft fits a wide range of Chevrolet vehicles originally equipped with flat tappet camshafts, including models like the 1967-1975 Chevrolet Bel Air, 1967-1972 Chevrolet Impala, and 1967-1972 Chevrolet Chevelle.

When installing this camshaft, remember that it's intended for engines originally equipped with flat tappet camshafts. If your engine has specific rear journal oiling requirements for 1965-66 396 models, this particular part number will not fit, and you'll need to contact COMP Cams directly for an alternative. Ensure you have the correct Melanized or Nitrided distributor gear on hand before starting installation to avoid any warranty issues.