Drag Race 4/7S 255/266 S-Flat Cam SBC

This COMP Cams Drag Race camshaft (Part Number 12-686-47) is designed for Chevrolet Small Block engines (262-400 c.i., 8 Cylinder, 1958-1998). It's a solid flat tappet camshaft intended for drag racing applications, requiring a 4000+ stall converter and 10.5:1 compression ratio or higher. The camshaft features a 4/7 swap firing order, a grind number of 47S 290B-6, and an operating RPM range of 4,000-7,000 RPM. Key specifications include 255 degrees intake duration at .050 inch lift, 266 degrees exhaust duration at .050 inch lift, 0.54 inches intake valve lift, and 0.534 inches exhaust valve lift. It has a 106-degree lobe separation angle. Lifters are not included, but valve springs and assembly lubricant are required. The camshaft is made from cast iron and has a 3-bolt camshaft gear attachment. Note on compatibility: For Chevrolet Small Block 1955-57 models, this camshaft will not fit if an oiling groove in the rear journal is required.