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Engines and Components› Camshafts and Valvetrain
Manley Performance
Manley Chevy L83 5.3L 1.560in Head Diameter Pro Flo/Extreme Duty Exhaust Valves (Set of 8)
SKU: M004 12363-8
Moderate — 2–4 hours
Overview
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Part #: 12363-8
Discover the extraordinary capabilities of Manley Performance Products' Extreme Duty Series Valves. Engineered to cater to the demanding needs of Top Fuel and Funny Car drag racers, Big Block Chevy marine enthusiasts, and Small Block Chevy restricted carburetor circle track competitors, these valves are your ticket to unparalleled performance.
Features:
- Ideal for Specialized Applications: Tailored for any application where extreme force and heat resistance is a must including Top Fuel, Funny Car, and Marine Engine applications.
- XH-432 XtremeAlloy: The hallmark of excellence in exhaust valve material construction.
- Built to Last: Featuring chrome stems and hard tips for exceptional longevity and wear resistance.
- Optimized Performance: Swirl polished under head areas and fully machined combustion faces improve airflow and combustion efficiency.
Manley Valve - Exhaust, Valve-E/D L83 5.3L 1.560, .3136 STEM.
This product may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.
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.
Fitment
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Specifications
| Brand | Manley Performance |
| Part Number | M004 12363-8 |
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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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