GrimmSpeed Radiator Cap (1.3 Bar), 2002-2014 WRX & 2004-2021 STi

Let's face it - engine cooling technology can sometimes seem like a dark magic that is impossible for us mortals to understand. That being said, it is well known that raising the pressure in your cooling system has a direct correlation to cooling performance. The factory 1.1 Bar (16 PSI) cap performs fine for daily driving with a system full of anti-freeze, but for those who are looking to push their Subaru harder or run on the track may be running an anti-freeze/water blend (or in many cases just straight distilled water) as it provides better heat transfer and dissipation than your standard coolant or antifreeze. The downside to running water or a blend of antifreeze/water is a lower boiling point and thus you would easily fill up (and in some cases overflow) your expansion tank within a couple of hot laps.
Upgrading the radiator cap to one with a higher pressure rating is the easiest (and by far the most economical) solution for solving this issue and keep your cooling fluid of choice where it belongs - in your engine and radiator. The GrimmSpeed High Pressure 1.3 Bar Radiator Cap is a high quality and way to maximize your cooling systems potential and upgrade the looks under your hood without breaking the bank!

Included:
• GrimmSpeed 1.3 Bar Radiator Cap - Subaru Universal

Features:
• 1.3 Bar/18.9 PSI Pressure Rated
• Increases Cooling System Efficiency
• Electro-coated Stamped Steel Construction
• Heavy-Duty Silicone Seal
• Understated Look Eliminates Ugly OEM Yellow Badge
• Manufactured in Japan