What makes these valves 'Extreme Duty'?

These valves are constructed from XH-432 XtremeAlloy and feature chrome stems and hard tips. This combination is designed to withstand higher forces and temperatures than standard valves, making them suitable for demanding engine applications.

How do the swirl polished and machined faces help?

The swirl polished area under the head and the fully machined combustion faces are designed to optimize airflow into the cylinder. This can lead to improved combustion efficiency and better overall engine performance.

Are these valves sold individually or as a set?

This product listing is for a single exhaust valve. If you are rebuilding your engine, you will need to purchase the appropriate quantity for all exhaust ports.

Specifications

Brand: Manley Performance
Part #: 11139-1
UPC: 807298051031

Manley 00-03 Subaru WRX (EJ20) / 04 STi Exhaust 33mm Stainless Extreme Duty Valve (1 valve)

Name: Manley 00-03 Subaru WRX (EJ20) / 04 STi Exhaust 33mm Stainless Extreme Duty Valve (1 valve)
Brand: Manley Performance
SKU: manley-performance-manley-00-03-subaru-wrx-ej20-04-sti-exhaust-33mm-stainless-ex-t14-251313
Price: 74.57 USD
Availability: BackOrder

$74.57

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Fits 2002-2012 Subaru Impreza. Manley Extreme Duty exhaust valve made from XH-432 XtremeAlloy for improved heat and force resistance.

Key Features

Fits 2002-2012 Subaru Impreza and 2005-2006 Saab 9-2X.
Constructed from XH-432 XtremeAlloy, a material known for extreme force and heat resistance.
Features chrome stems and hard tips for enhanced longevity and wear resistance.
Swirl polished under head areas and fully machined combustion faces improve airflow and combustion efficiency.
33mm stainless steel construction for durability.

⚠️ CA WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. Learn more

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About this part

Product Details

Starting with the XH-432 XtremeAlloy material, these Manley Extreme Duty exhaust valves are built for tough conditions. They are designed to handle the extreme forces and heat found in high-performance applications, making them a solid choice when you need something more robust than a standard valve. The 33mm stainless steel construction is a key part of their durability.

Beyond the material, these valves feature chrome stems and hard tips, which adds to their longevity and resistance to wear, especially in demanding engine builds. The under-head area is swirl polished, and the combustion faces are fully machined. These details help improve airflow into the cylinder and can contribute to more efficient combustion.

While these valves are built for extreme applications, they also fit directly into your 2002-2012 Subaru Impreza, offering an improved option for those rebuilding or modifying their engine. If you're working on a high-output EJ20 or similar engine, these valves are a well-built component to consider.