Manley Severe Duty series performance valves are a great choice for your high performance or race engine. All valves are made from stainless steel (intakes are NK-844; exhausts are XH-428) with chrome stems and hardened valve tips. Severe Duty series valves are made of superior materials, are fully machined and swirl polished, and are available with either undercut "Pro Flo" stems or straight stems.

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MANLEY Valve, Extreme Duty, Exhaust, 31.5mm in. Head Dia., 0.2345 in. Stem Dia., 4.274 in. Length, For Ford 5.0L, Set of 8

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MANLEY Valve, Extreme/Severe Duty, Exhaust, 1.496 in. Head Dia., 0.274 in. Stem Dia., 5 in. Length, Gen II, Set of 8

MANLEY Valve, Extreme/Severe Duty, Exhaust, 1.496 in. Head Dia., 0.274 in. Stem Dia., 5 in. Length, Gen II, Set of 8

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MANLEY Valve, Severe Duty, Exhaust, 1.6 in. Head Dia., 0.3415 in. Stem Dia., 5.565 in. Length, SBC, Each

MANLEY Valve, Severe Duty, Exhaust, 1.6 in. Head Dia., 0.3415 in. Stem Dia., 5.565 in. Length, SBC, Each

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MANLEY Valve, Race Master, Intake, 37mm Head Dia., 0.275 in. Stem Dia., 5.339 Length, For Ford, Set of 8

MANLEY Valve, Race Master, Intake, 37mm Head Dia., 0.275 in. Stem Dia., 5.339 Length, For Ford, Set of 8

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MANLEY Valve, Titanium, Intake, Bead Loc, 2.1 in. Head Dia., 0.3135 in. Stem Dia., 5.08 in. Length, Set of 8

MANLEY Valve, Titanium, Intake, Bead Loc, 2.1 in. Head Dia., 0.3135 in. Stem Dia., 5.08 in. Length, Set of 8

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MANLEY Valve, Titanium, Intake, 2.25 in. Head Dia., 0.3415 in. Stem Dia., 5.35 in. Length, Set of 8

MANLEY Valve, Titanium, Intake, 2.25 in. Head Dia., 0.3415 in. Stem Dia., 5.35 in. Length, Set of 8

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