Engines and Components› Camshafts and Valvetrain

Manley Performance

Manley Chevrolet Big Block Exhaust Valve Kit - 1.800in Head Dia. 5.930in O/A Length, 0.3415in Stem

$636.03

SKU: M004 12343-8

In Stock
In Stock
Ships by Jun 20
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

Engineered for high-temperature gasoline engines, this exhaust valve kit features Manley's Severe Duty® design, delivering exceptional durability and performance. Crafted from XH-428 material, the valves offer nearly double the ultimate tensile strength at 1500°F compared to competitors. Chrome stems and hard tips enhance longevity, while swirl polished under head areas and fully machined combustion faces optimize airflow and combustion efficiency.

Fitment

Fitment Guaranteed

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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

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Specifications

BrandManley Performance
Part NumberM004 12343-8

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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