These Severe Duty Gen II custom valves with unmatched strength and superiority are the only valves of their kind. Exhaust material XH-428 and intake material NK-844 are paired together for ultimate dominance over all others. With four times the tensile strength of competitors' intake valves and supremely better fatigue life, Manley Severe Duty Gen II custom valves truly show their commitment to seeing that you're there at the finish. You decide the head diameter and seat and margin widths, as well as valve length, groove type, and location for the perfect custom setup!

More From This Category

Trick Flow Valve, Intake, Stainless Steel, 2.055 in. Diameter, .314 in. Stem, 5.200 in. Length, Small For Ford, Each

Trick Flow Valve, Intake, Stainless Steel, 2.055 in. Diameter, .314 in. Stem, 5.200 in. Length, Small For Ford, Each

$56.52

MANLEY Valve, Street Flo, Exhaust, 1.6 in. Head Dia, 0.3415 in. Stem Dia, 5.065 in. Length, SBC, Set of 8

MANLEY Valve, Street Flo, Exhaust, 1.6 in. Head Dia, 0.3415 in. Stem Dia, 5.065 in. Length, SBC, Set of 8

$280.36

Sonnax Oversized Secondary Pressure Regulator Valve Kit, A340E, A340H, Each

Sonnax Oversized Secondary Pressure Regulator Valve Kit, A340E, A340H, Each

$89.36

MANLEY Valve, Street Flo, Intake, 2.08 in. Head Dia, 0.3415 in. Stem Dia, 5.04 in. Length, SBC, Each

MANLEY Valve, Street Flo, Intake, 2.08 in. Head Dia, 0.3415 in. Stem Dia, 5.04 in. Length, SBC, Each

$35.04

MANLEY Valve, Severe Duty, Exhaust, 1.88 in. Head Dia, 0.3415 in. Stem Dia, 5.522 in. Length, BBC, Set of 8

MANLEY Valve, Severe Duty, Exhaust, 1.88 in. Head Dia, 0.3415 in. Stem Dia, 5.522 in. Length, BBC, Set of 8

$607.34

MANLEY Valve, Race Flo, Intake, 1.84 in. Head Dia, 0.3415 in. Stem Dia, 4.911 in. Length, SBC, Each

MANLEY Valve, Race Flo, Intake, 1.84 in. Head Dia, 0.3415 in. Stem Dia, 4.911 in. Length, SBC, Each

$47.58