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Manley Chevrolet Big Block 2.300 Head Dia .5.494in Stem Severe Duty Intake Valve - Single

SKU: MAN12854-1

Valves

MAN Severe Duty Valves...

Manley Chevrolet Big Block 2.300 Head Dia .5.494in Stem Severe Duty Intake Valve - Single

SKU: MAN12854-1

Valves

MAN Severe Duty Valves...

A$96.39
Available from MFR. This item is available from the manufacturer's distribution centre. The dispatch timeframe shown is an estimate based on historical order processing and release times for this part. This item is not held in our own warehouse, and actual dispatch timing may vary depending on manufacturer workload and logistics at the time of ordering.
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Description

Manley Severe Duty® Valves deliver the ultimate in strength, reliability, and high-performance durability. Engineered for extreme gasoline engine temperatures, these valves are crafted from exclusive materials (XH-428 for exhaust and NK-844 for intake), offering unmatched tensile strength compared to competitive alloys. In fatigue testing at 40,000 psi and 1400°F, Manley exhaust valves endured 100 million cycles, while competitors failed after just 100,000, proving a 1,000× longer fatigue life. Each valve features chrome stems, hard tips, and swirl-polished underheads with fully machined combustion faces for superior airflow, efficiency, and wear resistance. Built for those who demand race-winning strength and precision, Manley Severe Duty® Valves set the industry standard for performance and endurance.

Part Type

Engine Intake Valve

Data: v4.2 - Upd: 2026-10-13 17:06:30

Features

  • Chrome stems and hard tips enhance durability
  • Exotic alloys for superior tensile strength, reliability, and longevity
  • Proven fatigue strength for extreme performance
  • Swirl polishing and machined faces improved airflow/optimized efficiency

Specifications

Product Attributes - Brand
Manley
Product Attributes - Manufacturer's Part Number
12854-1
Product Attributes - Part Type
Valves
Product Attributes - Product Line
Manley Severe Duty Series Stainless Steel Valves
Product Attributes - UPC
807298005812
Product Attributes - Valve Position
Intake
Product Attributes - Intake Valve Head Diameter (in.)
2.300 in.
Product Attributes - Intake Valve Head Diameter (mm)
58.420mm
Product Attributes - Intake Valve Stem Diameter (in.)
0.311 in.
Product Attributes - Intake Valve Stem Diameter (mm)
7.90mm
Product Attributes - Intake Overall Valve Length (in.)
5.494 in.
Product Attributes - Intake Overall Valve Length (mm)
139.548mm
Product Attributes - Undercut Stem
No
Product Attributes - Swirl-Polished
Yes
Product Attributes - Valve Tip Length (in.)
0.250 in.
Product Attributes - Valve Tip Length (mm)
6.350mm
Product Attributes - Valve Material
Stainless steel
Product Attributes - Lock Groove Quantity
1-groove
Product Attributes - Lock Groove Style
Beadlock
Product Attributes - Approximate Weight (g)
130
Product Attributes - Valve Head Style
5 degree dish
Product Attributes - Valve Seat Width (in.)
0.080 in.
Product Attributes - Quantity
Sold individually.
Product Attributes - Notes
Under head angle/radius 10 x 3/8 in.

Reference Information

Brand Name/s Manley Performance
StreetFX SKU man12854-1
SFX Item ID 4061695
Supplier Item Code 4061695
Manufacturer SKU 12854-1
Manufacturer UPC 807298005812
Alternative References .5.494in

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