Manley Severe Duty Pro Flo 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 offer improved flow with undercut "Pro Flo" stems.

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MANLEY Valve, Extreme/Severe Duty, Exhaust, 1.654 in. Head Dia., 0.3136 in. Stem Dia., 5.75 in. Length, Gen II, Set of 8

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Trick Flow Valve, Intake, Stainless Steel, 1.840 in. Diameter, 7.0mm Stem, 118.11mm Length, For Ford 4.6L/5.4L, Each

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MANLEY Valve, Severe Duty, Exhaust, 1.625 in. Head Dia., 0.3415 in. Stem Dia., 5.365 in. Length, SBC, Set of 8

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MANLEY Valve, Custom, Titanium, .3415 in. Stem Dia., Set of 8

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MANLEY Valve, Intake, Bead Loc, 2.5 in. Head Dia., 0.3415 in. Stem Dia., 6.475 in. Length, Set of 8

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