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Manley 12335-8 Severe Duty Engine Exhaust Valve Set — 1.600 in. Head, 0.3136 in. Stem (8-Pack)

Manufacturer

Picture for manufacturer Manley

Part Number

12335-8
13 reviews
Sale Price

$301.07

In Stock (6)

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Product Details

The Manley 12335-8 Severe Duty® Engine Exhaust Valves deliver race-proven strength and precision engineering for high-performance small block Chevrolet applications. Manufactured from Manley's exclusive XH-428 exhaust alloy, these stainless steel valves offer tensile strength that outperforms conventional competitive alloys. In fatigue testing at 40,000 psi and 1,400°F, Manley's exhaust valves sustained 100 million cycles — a 1,000× longer fatigue life than valves that failed after just 100,000 cycles under the same conditions. This kit includes 8 exhaust valves sized with a 1.600 in. head diameter, 0.3136 in. stem diameter, and 4.950 in. overall length, designed to suit AFR cylinder heads.

Key Features:

  • Manufactured from XH-428 exclusive exhaust alloy for superior tensile strength and longevity
  • Fatigue-tested to 100 million cycles at 40,000 psi and 1,400°F — extreme-duty rated
  • Chrome stems and hard tips for enhanced wear resistance and durability
  • Swirl-polished underheads and fully machined combustion faces for optimized airflow and combustion efficiency
  • 18-degree dish valve head shape with 25.00° underhead angle and 7/16 in. underhead radius
  • Head diameter: 1.600 in. | Stem diameter: 0.3136 in. | Overall length: 4.950 in.
  • Tip length: 0.260 in. | Margin width: 0.070 in. | Seat width: 0.100 in.
  • Compatible with AFR cylinder heads on small block Chevrolet engines
  • Kit quantity: 8 exhaust valves

Manley Severe Duty® Valves are the benchmark for performance engine builders who demand race-winning durability and precision. Designed specifically for extreme gasoline engine temperatures and high-RPM operation, this set is built to outlast and outperform in even the most demanding applications. Fits select Chevrolet small block engines equipped with AFR cylinder heads.

so far excellent..quick check out time!

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insufficient info presented. Before confirming payment needed to make sure part fit proper side. Info not provided had to call in waited ten minutes. Also when choosing paypal payment it wouldn't transfer. had to log off twice before final completion.

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I searched and searched and could not find a good price then i found Autoplicity and gave it a try, i couldn't believe i found my headers i wanted at an incredible low price, let alone the shipping was at a fair price even total price was lower than ebay or other places, definitely keeping this site on my sights for new parts and other products im keeping in mind!

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