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Manley 11745-8 Extreme Duty Stainless Steel Exhaust Valves Big Block Chevy

Manufacturer

Picture for manufacturer Manley

Part Number

11745-8
7 reviews
Sale Price

$514.08

2 left at this price

delivery box

Usually delivered within 2 days

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Fitment guaranteed

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Product Details

The Manley 11745-8 Extreme Duty Exhaust Valves are a premium-grade valvetrain component engineered for Big Block Chevy engines demanding maximum durability and thermal resistance. Constructed from XH-432 XtremeAlloy stainless steel with chrome stems and hardened valve tips, these valves are purpose-built for bracket racing, oval track, and high-performance street applications.

Key Specifications:

  • Valve Position: Exhaust
  • Head Diameter: 1.900"
  • Stem Diameter: 11/32" (0.3415")
  • Overall Length: 5.422" (Stock Height)
  • Underhead Angle/Radius: 15° x 1/2"
  • Top of Head: 9° Dish
  • Material: XH-432 XtremeAlloy Stainless Steel
  • Stem Finish: Hard-coated Chrome
  • Tip: Hardened

Key Features:

  • XH-432 XtremeAlloy stainless steel construction for superior high-temperature strength and fatigue resistance
  • Chrome-coated stems for reduced wear and improved lubrication retention
  • Hardened valve tips resist rocker arm wear under high-lift, high-rpm conditions
  • Swirl polished and fully machined for precision fit and optimal flow characteristics
  • Stock installed height for straightforward drop-in installation

Manley Performance is a trusted name in professional racing and high-performance engine building. The Extreme Duty series represents their top-tier valve offering, delivering the strength and reliability needed to withstand the demands of forced induction, nitrous, and high-compression race engine builds.

Products specifications

Approximate Weight (g)

136

Lock Groove Quantity

1-groove

Lock Groove Style

Conventional

Notes

Underhead angle/radius 15 x .500 in. Margin 0.075 in. Also designed to work in marine applications.

Overall Valve Length (in)

5.422 in.

Overall Valve Length (mm)

137.719mm

Quantity

Sold as a set of 8.

Swirl-Polished

Yes

Undercut Stem

Yes

Valve Head Diameter (in)

1.900 in.

Valve Head Diameter (mm)

48.260mm

Valve Head Style

9 degree dish

Valve Material

XH-432 Xtreme alloy

Valve Seat Width (in)

0.085 in.

Valve Stem Diameter (in)

0.342 in.

Valve Stem Diameter (mm)

8.687mm

Valve Tip Length (in)

0.250 in.

Valve Tip Length (mm)

6.350mm

Good service so far thanks Wasn;t the fix we needed but we tried.

Great pricing. (Check on google and they were the cheapest and had great reviews.) Quick shipment and everything is as they said it would be.

Quick, and easy and great prices

good website..easy to find parts.......great prices

Good pricing and easy ordering

The only recommendation I have is to include the position in the description for brake pads. I had to check another site to verify front vs. rear pads. It's not a major issue, especially because you have some of the best prices on these pads.

Easy

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