Manley Chevrolet Big Block Exhaust Valve Kit - 1.880in Head Dia. 5.522in O/A Length, 0.3415in Stem

If you're rebuilding the top end of a Chevrolet big block engine, especially one that sees hard use, these Manley Severe Duty? exhaust valves are a solid choice. They're made from XH-428 material, which Manley says has nearly double the tensile strength at 1500?F compared to other common exhaust valve materials like EV-8. This means they can handle the intense heat and stress inside a high-performance gasoline engine much better than standard valves.

These valves are built for durability. They feature chrome stems and hard tips to resist wear, and the under-head areas are swirl polished to help improve airflow into the cylinder. The combustion faces are also fully machined for better efficiency. Manley put these valves through some serious testing, reporting that they endured up to 100 million cycles at 40,000 psi and 1400?F, which is a notable improvement over other valves that failed much sooner.

This kit includes exhaust valves with a 1.880-inch head diameter, a 5.522-inch overall length, and a 0.3415-inch stem diameter. They are designed to fit right into your Chevrolet big block cylinder heads.