Brand New Subaru WRX STI B25 Cylinder Head Premium Aftermarket Loaded (Left)

Product Description:
Upgrade your engine with a brand new Subaru WRX STI B25 left cylinder head, designed specifically for 2004-2005 Subaru Baja, Forester, Impreza, and 2005-2006 Legacy GT 2.5L turbocharged engines. This Subaru WRX STI B25 left cylinder head is premium, fully assembled, and engineered for maximum performance. It comes with all necessary components, such as valves, springs, and cams, already installed, making it ready for quick installation.

This brand new Subaru WRX STI B25 left cylinder head is crafted from high-quality materials for enhanced durability and optimized airflow, ensuring your turbocharged engine runs smoothly and efficiently. Whether you’re performing a rebuild or upgrading your engine, this cylinder head will help improve performance, reduce maintenance issues, and extend the life of your engine.

Key Features:

• Fitment: Compatible with 2004-2005 Subaru Baja (2.5L, 4-cylinder, w/turbo), 2004-2005 Subaru Forester (w/turbo), 2004-2005 Subaru Impreza (2.5L, w/turbo), and 2005-2006 Subaru Legacy GT (2.5L, DOHC).
• Premium Aftermarket Quality: Built for performance and durability, ideal for rebuilding or upgrading turbocharged Subaru engines.
• Fully Assembled: Ready for installation with all essential components like valves, springs, and cams.
• Optimized for Turbocharged Engines: Perfect for 2.5L turbocharged Subaru engines, improving airflow and engine efficiency.
• Durability Guaranteed: Manufactured from high-quality materials for long-lasting reliability.
• Core Return Required

Fitment Data:

• Subaru Baja: 2004-2005 2.5L, 4-cylinder, w/turbo (Left Cylinder Head)
• Subaru Forester: 2004-2005 w/turbo (Left Cylinder Head)
• Subaru Impreza: 2004-2005 2.5L, w/turbo (Left Cylinder Head)
• Subaru Legacy GT: 2005-2006 2.5L, DOHC (Left Cylinder Head)

Important Information:

• This is the left cylinder head for turbocharged 2.5L engines.
• Ensure your vehicle matches the fitment details before purchasing.

Why Choose Our Premium Aftermarket Loaded Left Cylinder Head?

• Ready for Installation: All components are pre-assembled for quick and easy installation.
• Engineered for Maximum Performance: Designed to optimize airflow and efficiency in your 2.5L turbocharged Subaru engine.
• Built to Last: Constructed from premium materials for optimal reliability and long-term performance.
• Cost-Effective: Save on labor costs with a fully assembled cylinder head that provides excellent value for the performance boost it offers.
• Warranty Included: Comes with a warranty for added peace of mind.

Heavy Duty Parts Company – Core Returns Policy

Effective December 17, 2025

At Heavy Duty Parts Company, core returns are essential to our ability to provide high-quality, cost-effective cylinder heads. Returned cores supply critical components—such as keepers, springs, and retainers—that are vital to proper engine performance and allow us to maintain OEM-level quality.

No Upfront Core Charge

Unlike many suppliers, we do not charge a core fee upfront. Instead, we rely on customers to return their used cores within the required timeframe.

Core Return Requirements

• Cores are due within 30 days of the purchase date

• If a core is not returned within 60 days, the product warranty is void

• Unreturned cores will be charged as follows:

  • Cylinder heads under $600: $200 per unreturned core

  • Cylinder heads $600 and above: $400 per unreturned core

Customers needing additional time may contact us to request an extension. Approved extensions will prevent core charges from being applied.

Core Return Process

Cylinder heads are shipped with prepaid core return labels included in packets attached to the outside of each box. If labels are missing, customers should contact us for replacements prior to returning the core.

Core Eligibility

Some cylinder heads do not require a core return. In certain cases, core requirements may be waived at our discretion.

Why Core Returns Matter

• Reused core components help maintain OEM-quality standards

• Core returns allow us to keep pricing competitive

• Recycling cores supports sustainability by reducing waste and conserving resources

This policy applies to all purchases made on or after December 17, 2025.

Send Back All Components

To ensure the quality and integrity of our remanufacturing process, we ask that you return all components that were originally included with your new cylinder head. This includes items such as:

• Rocker arms
• Camshafts (if applicable)
• Any other hardware that came with your purchase

Easy & Free Core Return Process

• Each purchase includes a prepaid core return label in a plastic sleeve on the box.
• Simply pack your core with all included components, attach the label, and drop it off with the carrier—no extra cost to you.
• Returned cores undergo inspection and recycling, ensuring maximum efficiency.

Customer Partnership & Sustainability

By returning your core and its components, you help maintain a reliable supply chain, ensuring we can continue offering top-quality products at the best prices. This process not only benefits your wallet but also contributes to a greener and more efficient automotive industry.

We appreciate your support in keeping our business and the industry running smoothly!

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