COMP Cams Camshaft Kit CS XR300HR-10

This COMP Cams kit gives you everything you need to install the Xtreme Energy XR300HR-10 camshaft into your Chevrolet Small Block engine. Inside this box, you'll find the camshaft itself, a set of hydraulic roller lifters, a complete timing chain set, assembly lube to get everything started right, and some decals. This kit is designed for performance applications like pro street and bracket racing, aiming for around 10:1 compression and requiring a 3500+ stall torque converter. Expect a very rough idle with this aggressive camshaft profile.

The XR300HR-10 camshaft features a 248-degree intake duration and a 254-degree exhaust duration at .050 inch lift, with a .571 inch intake lift and .578 inch exhaust lift. This camshaft is intended for use with hydraulic roller lifters and is specifically designed for Gen 1 Small Block Chevrolet engines. It's important to verify your engine's setup, as this kit is for engines with flat tappet camshafts. GM began phasing in factory roller camshafts in the mid-1980s, so you may need to remove the intake manifold or timing cover to confirm if your block is equipped for a factory roller setup. This kit is not compatible with LT1/LT4 engines or any LS-based V8s.

For optimal performance, this camshaft kit works well with a good intake manifold and headers. It's also recommended for engines with 10:1 compression and a torque converter with a stall speed of 3500 RPM or higher. Note that this kit is not CARB approved and cannot be shipped to California. For 1955-1957 Chevrolet 265 engines, ensure there is a groove on the 5th cam journal for proper oiling; contact COMP Cams for more details if needed.