Replace the fragile factory plastic component with the Koyo Aluminum Filler Neck (FN3037), engineered specifically for the 2022 Toyota GR86 and Subaru BRZ. High-performance cooling systems often experience increased pressure and thermal cycles that can cause original equipment plastic filler necks to crack or warp over time, leading to coolant loss and potential overheating issues.

• Direct replacement for the OEM plastic filler neck unit
• Constructed from high-grade aluminum for superior durability and heat resistance
• Precision-machined for a perfect fit with factory hoses and radiator caps
• Eliminates a common failure point in the cooling system
• Manufacturer Part Number: FN3037

This aluminum filler neck is a vital upgrade for drivers who track their vehicles or live in hot climates, ensuring the integrity of the cooling system under demanding conditions.

Upgrade your cooling system's reliability with the Koyo Aluminum Filler Neck (FN2320), specifically engineered for the 2013-2016 Scion FR-S and Subaru BRZ. The factory plastic filler neck is a well-documented weak point in the ZN6/ZC6 platform, often becoming brittle and prone to cracking after repeated heat cycles. This Koyo component provides a robust, permanent solution for both daily driven and track-oriented vehicles.

Constructed from high-grade aluminum with precision TIG welding, this filler neck is a direct-fit replacement that bolts into the factory mounting position. It is designed to work seamlessly with original equipment cooling system components and maintains compatibility with standard radiator caps.

• Direct replacement for the failure-prone factory plastic filler neck
• Durable TIG-welded aluminum construction for superior heat resistance
• Ensures long-term cooling system integrity and prevents leaks
• Fits 2013-2016 Scion FR-S and Subaru BRZ
• Manufacturer Part Number: FN2320

The Vibrant Performance 20982 Weld-On Radiator Filler Neck is precision-engineered for custom cooling system fabrication. CNC machined from high-strength 6061 aluminum alloy, this filler neck provides a clean, weldable surface for custom aluminum radiators or expansion tanks. It comes equipped with a removable barbed nipple for straightforward plumbing to an external overflow tank.

• Material: CNC Machined 6061 Aluminum Alloy
• Inside Diameter: 42mm (1.65in)
• Configuration: Weld-on application
• Hardware: Includes barbed nipple fitting for overflow line integration
• Compatibility: Optimized for Vibrant Performance high-pressure aluminum radiator caps
• Replacement Barb Fitting: Part #11642F
• Manufacturer Part Number: 20982

The Vibrant Performance 20980 Weld-On Radiator Filler Neck is engineered for custom cooling system fabrication and high-performance radiator builds. Precision CNC machined from 6061 aluminum alloy, this component offers excellent weldability and a consistent sealing surface for high-pressure applications.

Designed for professional-grade plumbing, the neck features an integrated barbed nipple for easy connection to an expansion or overflow tank. This filler neck is specifically designed to be compatible with Vibrant Performance high-pressure aluminum radiator caps, ensuring a secure and reliable fit under thermal stress.

• Part Number: 20980
• Material: CNC Machined 6061 Aluminum Alloy
• Inner Diameter: 32mm (1.25in)
• Included Ports: Integrated overflow/expansion tank barbed nipple
• Compatibility: Designed for Vibrant Performance High-Pressure Caps
• Serviceable Parts: Uses replacement hose barb fitting #11642F

The Moroso 63486 Weld-On Filler Neck is precision-engineered for custom fabrication projects requiring a reliable coolant fill point. CNC-machined from high-quality billet aluminum, this component is designed to be welded directly onto custom aluminum radiators, expansion tanks, or coolant recovery canisters.

• Manufacturer Part Number: 63486
• Material: CNC-machined billet aluminum
• Attachment Style: Weld-on
• Compatibility: Designed to accept standard-size radiator caps
• Application: Ideal for custom cooling system builds and tank fabrication

The raw aluminum finish ensures excellent weldability and a professional appearance. By utilizing a billet construction rather than a casting, this filler neck provides superior dimensional stability and a clean sealing surface for the radiator cap pressure plunger and upper seal.

The Mishimoto MMFN-S CNC-Machined Aluminum Radiator Fill Neck is an essential component for custom cooling system fabrication. Engineered for builders manufacturing their own aluminum radiators or expansion tanks, this 32mm fill neck provides a precision-engineered interface for pressure regulation and coolant management.

Each unit is CNC-machined from high-quality aluminum, ensuring a clean, burr-free finish that is ready for TIG welding directly to your custom project. This small-style (32mm) fill neck is designed for full compatibility with Mishimoto radiator caps and includes a dedicated screw-in nipple for an overflow hose connection.

• Precision CNC-machined aluminum construction for superior weldability
• Small-style 32mm neck diameter
• Includes screw-in nipple for overflow tank routing
• Compatible with Mishimoto high-pressure radiator caps
• Designed for custom radiator, expansion tank, or header tank fabrication
• Mishimoto Part Number: MMFN-S

Engineered for custom radiator fabrication and cooling system builds, the Mishimoto Large 42mm Aluminum CNC Coolant Fill Neck provides a precision-machined solution for your next project. This universal component is CNC-machined from high-grade aluminum, ensuring a clean surface that is ready to be welded directly onto custom aluminum radiators or expansion tanks.

This fill neck is specifically designed for compatibility with Mishimoto Radiator Caps and features a 42mm bore. To simplify plumbing, it includes a screw-in nipple for an overflow line, allowing for easy connection to your recovery tank. Whether you are building a custom race radiator or a one-off cooling setup, this fill neck delivers the fitment and durability required for professional-level fabrication.

• CNC-machined aluminum construction for clean welding and long-term durability
• Large 42mm size designed for high-performance custom applications
• Includes threaded screw-in nipple for overflow plumbing
• Compatible with Mishimoto Radiator Caps
• Manufacturer Part Number: MMFN-L

Fits select 2008-2017 Mitsubishi Lancer (including Evolution and Ralliart models) and 2011-2019 Outlander Sport.

Replace your vehicle's failure-prone plastic coolant neck with the Mishimoto All-Aluminum Coolant Fill Inlet. Designed for lasting durability, this unit eliminates the risk of leaks associated with aged OEM plastic components that become brittle and crack over time. This fill inlet is CNC cut and bent for precise fitment, ensuring a direct-fit installation with both factory rubber hoses and Mishimoto silicone replacement hoses.

The MMFN-EVO-RD features a vibrant red powder-coated finish for maximum corrosion resistance and a custom look under the hood. To ensure a complete and reliable seal, Mishimoto includes a replacement radiator cap with every unit, all backed by their signature Lifetime Warranty.

• Full aluminum construction prevents cracking and leaks common with factory plastic inlets
• CNC-machined and bent to ensure proper sizing and factory-level fitment
• Durable red powder-coated finish for longevity and aesthetics
• Direct-fit for OEM hoses and Mishimoto silicone replacement hoses
• Includes replacement radiator cap
• Manufacturer Part Number: MMFN-EVO-RD
• Mishimoto Lifetime Warranty

Upgrade your cooling system's reliability with the Mishimoto Coolant Fill Inlet. Fits select 2008-2017 Mitsubishi Lancer and 2011-2019 Mitsubishi Outlander Sport models. This component is designed as a high-durability alternative to the failure-prone factory plastic inlet, providing a robust solution for enthusiasts and daily drivers alike.

The MMFN-EVO-BK is manufactured from all-aluminum and is CNC cut and bent to ensure precise sizing and flow. The unit is finished with a durable black powder coating for long-lasting corrosion resistance and a clean look in the engine bay. It is engineered for a direct-fit installation, accommodating both factory OEM hoses and Mishimoto silicone replacement hoses. Each kit includes a replacement cap to ensure a complete and secure seal.

• All-aluminum construction replaces weak factory plastic components
• CNC cut and bent for precise fitment and optimal coolant routing
• Durable black powder-coated finish for maximum longevity
• Compatible with both OEM and Mishimoto silicone radiator hoses
• Includes a new replacement fill cap
• Backed by the Mishimoto Lifetime Warranty
• Manufacturer Part Number: MMFN-EVO-BK

Fits 2006-2011 Honda Civic models.

Engineered for durability and precision, the Koyo Aluminum Filler Neck (FN2313) provides a robust replacement for factory cooling system components. Constructed from high-grade aluminum, this filler neck is designed to withstand the thermal stresses and pressures of performance driving while offering a cleaner, more professional look in the engine bay.

• Material: High-grade aluminum for superior heat and corrosion resistance
• Installation: Direct fit for specified Honda Civic applications
• Part Number: FN2313
• Required Accessory: Must be used with an SK-C13 or equivalent deep plunger style radiator cap (sold separately)