Engines and Components› Camshafts and Valvetrain

Manley

Stainless Steel Valves, Chrome Stems

$52.99

SKU: 660-11686-8

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Overview

Manufactured from NK-842 stainless steel, these valves feature chrome stems and hard tips. They are designed with GM LS OEM-style radius keeper grooves and are swirl polished with Pro Flo Technology for enhanced flow.
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The Manley Severe Duty® Series intake valves are a top-tier component for high-performance engine builds, designed for applications below 8000 RPM. These valves are constructed from advanced NK-842 stainless steel for intake and XH-428 for exhaust, ensuring superior strength and heat resistance. The intake valves feature a 2.165-inch head diameter and a 0.3133-inch stem diameter, with an overall length of 4.900 inches. They are equipped with chrome stems and hard tips for enhanced durability and longevity, and utilize GM LS OEM-style radius keeper grooves. Engineered with Pro Flo Technology, these valves are swirl polished and have fully machined combustion faces to maximize airflow and improve combustion efficiency. Manley's Severe Duty® valves have demonstrated exceptional durability in rigorous fatigue testing, enduring up to 100 million cycles at high stress levels, significantly outperforming competitor offerings. They are specifically designed for high-temperature gasoline engines, offering nearly double the ultimate tensile strength at 1500°F compared to competing exhaust valve materials and over four times the strength of competitor intake valve materials at 1000°F. These valves are compatible with LS3/L92/LS99 cylinder heads and are a direct replacement designed to work with stock installed heights. Each set contains 8 intake valves.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandManley
Part Number660-11686-8
CategoryEngines and Components
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