Heating and Cooling› Radiators
Mishimoto
Mishimoto 08-09 Subaru WRX/STi Manual Aluminum Radiator
SKU: M00C MMRAD-STI-08
Moderate — 2–4 hours
Description
Part #: MMRAD-STI-08
Whether you're carving through back roads in your WRX or pushing your STI to the limit on track day, maintaining optimal coolant temperatures is essential to protecting your EJ engine. The factory radiator's plastic end tanks and limited cooling capacity can quickly become a weak link, especially under the high demands of spirited driving or hot summer commutes. A failure in the cooling system can lead to overheating, head gasket issues, and costly repairs that cut your driving adventures short. The Mishimoto Performance Aluminum Radiator for the 2008-2014 Subaru WRX and 2008-2021 Subaru STI is engineered to be the ultimate safeguard for your engine, delivering improved cooling efficiency and durability over stock. -- Built with a lightweight, dual-core design and 100% brazed aluminum construction, this radiator maximizes heat dissipation and withstands higher pressures to keep your engine performing at its best. The TIG-welded, polished end tanks add strength and a premium finish, while the direct-fit design ensures a straightforward installation with no cutting or modification required. The included high-pressure 1.3 bar radiator cap raises the boiling point of your coolant for an extra margin of safety under heavy loads, and a second radiator cap is included for use on the expansion tank. With up to a 30% increase in cooling efficiency over the factory unit, this upgrade is ideal for daily driving, spirited runs, or competitive use. -- Backed by the Mishimoto Lifetime Warranty, including accident protection, this radiator is built to keep your Subaru running strong for years to come.
Features:
- Direct fit for the 2008-2014 Subaru WRX/STI
- Premium radiator has 3-row (2" thick) core for improved strength and reliability.
- 16% thinner-than-stock tubes allow for more surface contact, increasing cooling efficiency.
- Greater density of rows for higher cooling capacity.
- More contact points for additional heat transfer.
- 3-row design creates more air turbulence, maximizing cooling efficiency
- Includes magnetic drain plug
- Includes a high-pressure 1.3 bar
- Mishimoto radiator cap
- Mishimoto Lifetime Warranty
Aluminum radiator engineered for efficient heat dissipation and optimal engine cooling. Precision-fit design ensures easy installation, corrosion resistance, and reliable performance across varied driving conditions.
MIA's Description
Fitment
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Specifications
| Brand | Mishimoto |
| Part Number | M00C MMRAD-STI-08 |
Videos
How to Install a high performance radiator in a WRX/ STI
Installing Mishimoto X-Line Radiator | Subaru WRX STI Cooling Upgrade
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Mishimoto Performance Aluminum Radiator fits 2001-2007 Subaru WRX/STI Installation Video
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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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