Manley Chevrolet Big Block Exhaust Valve Kit - 1.940in Head Dia. 5.522in O/A Length, 0.3415in Stem

This kit includes Manley's Severe Duty? exhaust valves, specifically designed for Chevrolet Big Block engines. Each valve features a 1.940-inch head diameter, a 5.522-inch overall length, and a 0.3415-inch stem diameter. These valves are crafted from XH-428 material, a robust alloy chosen for its exceptional strength at high temperatures, making them ideal for demanding gasoline engine applications.

Manley's Severe Duty? valves have undergone extensive fatigue testing, enduring up to 100 million cycles at 40,000 psi and 1400?F. This is a notable improvement over many competitor valves that can fail after only 100,000 cycles. The design includes swirl-polished under-head areas and fully machined combustion faces to help improve airflow and combustion efficiency. The chrome stems and hard tips add to their durability and longevity in high-stress environments.

If you're rebuilding the top end of a high-temperature gasoline engine, these valves offer a well-built option. The XH-428 material used for the exhaust valves provides nearly double the ultimate tensile strength at 1500?F compared to common EV-8 materials. For optimal performance and longevity in your Chevrolet Big Block, consider these robust exhaust valves.