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Manley 11685-8 Extreme Duty Stainless Exhaust Valve 1.590 in Head 8mm Stem LS3 L92

(2010 Chevrolet Camaro SS; 2008-2010 Chevrolet Corvette Base; 2009-2010 Chevrolet Corvette ZR1; 2010 Chevrolet Corvette Grand Sport; 2015-2023 Dodge Charger 4DR)

Manufacturer

Picture for manufacturer Manley

Part Number

11685-8
9 reviews
Sale Price

$514.08

In Stock (10+)

delivery box

Usually delivered within 2 days

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Product Details

The Manley 11685-8 Extreme Duty Series exhaust valves are engineered specifically for high-performance GM LS3, L99, and L92 cylinder head applications.

Key Specifications:

  • Head diameter: 1.590 inches
  • Stem diameter: 0.313 inches (8mm)
  • Overall length: 4.923 inches
  • Material: High-grade stainless steel with XH-432 alloy construction
  • Chrome-plated stems with hardened valve tips
  • GM LS OEM-style radius keeper grooves

Features and Benefits:

  • Extreme Duty Series construction provides superior heat resistance for forced induction and nitrous applications
  • Swirl-polished finish for maximum exhaust flow efficiency
  • Fully machined to precise tolerances for optimal sealing and performance
  • Chrome stems resist wear and provide extended service life
  • Hardened tips ensure durability under high-RPM operation

Manley Performance has been manufacturing premium racing engine components since 1966, and their Extreme Duty valves represent decades of racing experience and engineering excellence. These valves are ideal for street performance and racing applications operating below 8000 RPM.

Products specifications

Fits

2010 Chevrolet Camaro SS; 2008-2010 Chevrolet Corvette Base; 2009-2010 Chevrolet Corvette ZR1; 2010 Chevrolet Corvette Grand Sport; 2015-2023 Dodge Charger 4DR

Approximate Weight (g)

94

Lock Groove Quantity

1-groove

Lock Groove Style

Conventional

Overall Valve Length (in)

4.923 in.

Overall Valve Length (mm)

125.044mm

Quantity

Sold as a set of 8.

Swirl-Polished

Yes

Undercut Stem

Yes

Valve Head Diameter (in)

1.590 in.

Valve Head Diameter (mm)

40.386mm

Valve Head Style

18 degree dish

Valve Material

XH-432 Xtreme alloy

Valve Seat Width (in)

0.115 in.

Valve Stem Diameter (in)

0.314 in.

Valve Stem Diameter (mm)

7.976mm

Valve Tip Length (in)

0.160 in.

Valve Tip Length (mm)

4.064mm

Make

Chevrolet

Valve Head Diameter

1.590

Stem Diameter

0.3136

Engine Type

ICE

Product Type

Engine Exhaust Valve Kit

O/A Length

4.923

Seat Width

0.115

Top of Head

18 Degree Dish

Valve Stem Diameter

0.3136

Valve Type

Exhaust

Valve Length

4.923

Engine Valve Quantity

8

Underhead Angle

25.00

Underhead Radius

7/16

Valve Head Shape

18 Degree Dish

Valve Quantity

8

Margin Width

0.070

Valve Series

Extreme Duty Series

Head Diameter

1.590

Cylinder Head

L92 Cylinder Head

Tip Length

0.160

Valve Tip Length

0.160

Title

Manley Valve - Exhaust, Valve-L-92 E/D 1.590

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