Manley Chevrolet Small Block Exhaust Valve Kit - 1.600in Head Dia. 5.036in O/A Length, 0.3415in Stem

If you're rebuilding the top end of your Chevrolet small block engine, these exhaust valves from Manley Performance are a solid option. They are specifically made from XH-428 material, which is known for its strength at high temperatures, and are designed to handle the stresses of demanding engine operation. These valves measure 1.600 inches across the head and are 5.036 inches long overall, with a 0.3415-inch stem diameter, fitting precisely into your engine's cylinder head.

Manley put these Severe Duty? valves through some serious testing. They endured up to 100 million cycles at 1400 degrees Fahrenheit, which is a remarkable number compared to other valves that failed much sooner. This exceptional fatigue life means they are built to last under tough conditions. The design includes swirl-polished under-head areas and fully machined combustion faces to help improve airflow into the cylinder and make combustion more efficient. They also feature chrome stems and hard tips for added durability.

For engines running on gasoline and operating at high temperatures, these valves offer a well-built solution. The XH-428 material used for the exhaust valves has nearly double the tensile strength at 1500°F compared to other common exhaust valve materials. If you're looking for a robust valve that can withstand significant stress and heat, these are worth considering for your build.