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Manley Severe Duty Pro Flo Series Stainless Steel Valves 11686H-1 Valves, Intake, XH-428 Steel, 2.165 in. Diameter, .313 in. Stem, 4.900 in. Length, Chevy, Set of 8

SKU: MAN11686H-1

Valves

Manley Severe Duty Pro Flo Series Stainless Steel Valves 11686H-1 Valves, Intake, XH-428 Steel, 2.165 in. Diameter, .313 in. Stem, 4.900 in. Length, Chevy, Set of 8

SKU: MAN11686H-1

Valves
A$204.63
Special Order. Contact for ETA. This item is out of stock in our warehouse and partner distribution centres. In some cases, this may be due to not having live inventory feeds available for all suppliers. Please contact us before ordering if you need to meet a specific deadline.
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Description

Manley Severe Duty Pro Flo Series intake and exhaust 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 fully machined and swirl polished, and offer improved flow with undercut "Pro Flo" stems. Many size options are available, for applications from 1955 and up.

Part Type

Valves

Data: v4.2 - Upd: 2026-10-14 10:11:06

Specifications

Product Attributes - Brand
Manley
Product Attributes - Manufacturer's Part Number
11686H-1
Product Attributes - Part Type
Valves
Product Attributes - Product Line
Manley Severe Duty Pro Flo Series Stainless Steel Valves
Product Attributes - UPC
807298042886
Product Attributes - Valve Position
Intake
Product Attributes - Intake Valve Head Diameter (in.)
2.165 in.
Product Attributes - Intake Valve Head Diameter (mm)
54.991mm
Product Attributes - Intake Valve Stem Diameter (in.)
0.313 in.
Product Attributes - Intake Valve Stem Diameter (mm)
7.95mm
Product Attributes - Intake Overall Valve Length (in.)
4.900 in.
Product Attributes - Intake Overall Valve Length (mm)
124.460mm
Product Attributes - Undercut Stem
Yes
Product Attributes - Swirl-Polished
Yes
Product Attributes - Valve Tip Length (in.)
0.160 in.
Product Attributes - Valve Tip Length (mm)
4.064mm
Product Attributes - Valve Material
XH-428 stainless steel
Product Attributes - Lock Groove Quantity
1-groove
Product Attributes - Lock Groove Style
Conventional
Product Attributes - Approximate Weight (g)
118
Product Attributes - Valve Head Style
7 degree dish
Product Attributes - Valve Seat Width (in.)
0.100 in.
Product Attributes - Quantity
Sold individually.
Product Attributes - Notes
Hollow stem.

Reference Information

Brand Name/s Manley Performance
StreetFX SKU man11686H-1
SFX Item ID 4928613
Supplier Item Code 4928613
Manufacturer SKU 11686H-1
Manufacturer UPC 807298042886
Alternative References XH-428

Compatibility

Application Data
  • Valve FitmentSearch by engine
    MakeCHEVROLET
    Beginning Year2008
    Ending Year2017
    Engine TypeV8
    Engine Size6.2L/376
    Engine FamilyChevy small block Gen III/IV (LS-based engines)
    Valve Installed LengthStock
    Cylinder Head TypeL92
  • Valve FitmentSearch by engine
    MakeCHEVROLET
    Beginning Year2010
    Ending Year2017
    Engine TypeV8
    Engine Size6.2L/376
    Engine FamilyChevy small block Gen III/IV (LS-based engines)
    Valve Installed LengthStock
    Cylinder Head TypeL92

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