Cobb 08-14 Subaru WRX/STI Coolant Overflow Tank-COBB-COBB800655
Cobb 08-14 Subaru WRX/STI Coolant Overflow Tank-COBB-COBB800655
Cobb 08-14 Subaru WRX/STI Coolant Overflow Tank-COBB-COBB800655
Cobb 08-14 Subaru WRX/STI Coolant Overflow Tank-COBB-COBB800655
Cobb 08-14 Subaru WRX/STI Coolant Overflow Tank-COBB-COBB800655
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Cobb 08-14 Subaru WRX/STI Coolant Overflow Tank

COBB
COBB800655
700424681709
Coolant Reservoirs
10 Units In Stock - Ships Next Business Day
$ 290.00
$ 290.00

SKU: B800655   |   UPC: 700424681709

Cobb 08-14 Subaru WRX/STI Coolant Overflow Tank

The COBB Coolant Overflow Tank is a direct-fit replacement for the factory plastic reservoir on 2008-2014 Subaru WRX and STI models. Constructed from durable 6061-T6 billet aluminum, it resists cracking from repeated heat cycles common in performance driving. With 50% greater capacity than stock, it handles coolant expansion during track sessions or hard launches without spilling.

Key Features

  • Billet Aluminum Build: 6061-T6 material withstands high temperatures and pressure, outlasting plastic OEM tanks prone to failure.
  • Expanded Capacity: 50% larger volume captures excess coolant reliably, maintaining system integrity under boost.
  • Direct Bolt-On Design: Mounts in factory location using stock brackets, no cutting or fabrication needed.
  • Black Anodized Finish: Corrosion-resistant coating protects against engine bay elements for long-term durability.
  • Complete Kit: Includes laser-etched aluminum cap, AN fittings, and mounting hardware for straightforward install.

Product Notes

  • MPN 800655; replaces vulnerable OEM plastic tank on EJ-series engines.
  • Monitor coolant levels regularly during initial use after installation.
  • Packaged securely; shipping weight 1.9 lbs, box dimensions 10" x 8" x 4".

Installation Notes

  • Professional installation recommended.
  • Drain coolant system before removal; reuse OEM hoses if undamaged.
  • Secures to factory mounts with provided stainless steel hardware.

This Part Fits

Year Make Model Submodel
2008-2014 Subaru Impreza WRX
2008-2014 Subaru Impreza WRX STI

Why Choose COBB?

  • Decades of Subaru-specific engineering experience from grassroots racing origins.
  • Components tested on dynos and tracks for real-world reliability.
  • Made in USA with precision CNC machining for exact tolerances.

Frequently Asked Questions

  • Q: Will this fit 2015+ STI models?
    A: No, designed specifically for 2008-2014 WRX/STI with EJ25 engines; later models use different mounting.
  • Q: What material and finish are used?
    A: 6061-T6 billet aluminum with black anodized coating for heat resistance and engine bay protection.
  • Q: What is the warranty coverage?
    A: Backed by COBB's limited lifetime warranty against manufacturing defects when installed properly.

Shipping & Handling

  • Method: UPS Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Protective cardboard box, 10" x 8" x 4" dimensions
  • Weight: 1.9 lbs

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