Manley Oldsmobile 330 Exhaust Valve Kit - 1.710in Head Dia. 4.668in O/A Length, 0.3415in Stem

Starting with the XH-428 material, these Manley exhaust valves are built for serious performance in Oldsmobile 330 engines. This specific alloy is chosen for its exceptional strength at high temperatures, offering 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 of demanding gasoline engines without faltering.

Beyond the material, these valves are well-made with chrome stems and hard tips, adding to their overall durability and lifespan. The under-head areas are swirl polished to help with airflow, and the combustion faces are fully machined. This attention to detail contributes to improved airflow and more efficient combustion within the cylinder. Rigorous fatigue testing shows these valves can endure up to 100 million cycles at 40,000 psi and 1400°F, a notable improvement over many other valves that might fail after only 100,000 cycles.

This kit includes exhaust valves with a 1.710-inch head diameter and a 4.668-inch overall length, featuring a 0.3415-inch stem diameter. If you're rebuilding the top end of your Oldsmobile 330 and need valves that can withstand high temperatures and heavy use, these are a solid option.