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Radium Engineering AOS-R Kit w/ Master Cylinder Brace Subaru WRX | Forester XT 2014-2021
$474.95
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Radium Engineering AOS-R Kit with Master Cylinder Brace

Perfect Fit for Your Subaru WRX | Forester XT (2014-2021)

If you’re a Subaru enthusiast, you know that high-powered modified engines can sometimes produce a bit too much blow-by oil and gas. That’s where the Radium Engineering AOS-R Kit comes into play! Unlike a standard catch can that can fill up quickly and leave you wanting more, this Air Oil Separator (AOS) kit is designed specifically for your Subaru WRX or Forester XT, ensuring that all that excess oil and pollutants stay out of your intake pipe, manifold, turbocharger, and intercooler—no matter how hard you push your engine.

How It Works

The beauty of the AOS system is that it returns what it collects straight back into the oil pan, which means you won’t have to worry about servicing it regularly. Plus, it features a built-in heater that prevents water from condensing inside the AOS. Since water is denser than oil, there's also an integrated water trap at the bottom perimeter of the can. This clever design keeps any water that might sneak in from descending into the oil pan. Instead, it gets trapped against the heater, where it eventually boils away, keeping your system clean and efficient.

Key Benefits

  • Boosts fuel octane and improves engine performance by providing cleaner inlet air.
  • Prevents oil buildup in critical areas like the intake, intercooler system walls, throttle body, and intake manifold.
  • Reduces hydrocarbon emissions for a greener drive.

Installation Made Easy

Installing the Radium Engineering AOS kit is straightforward for your 2015+ Subaru WRX. It mounts on the left-hand side of the engine bay, right by the brake master cylinder. The outlet of the AOS is cleverly plumbed back to the turbo inlet pipe, creating a completely sealed system. To make it all fit perfectly, the AOS mounts to the Radium Brake Master Cylinder Brace, which is a must-have for installation. You’ll also replace the PCV valve with a custom machined straight-through adapter fitting, ensuring that any oil collected in the AOS drains back into the engine block smoothly.

Important Note

  • If you’re driving in freezing conditions, Radium Engineering recommends adding insulation sleeving (not included) over any hoses exposed to cold air. This will help prevent water condensation from freezing and potentially clogging your hoses.

Compatibility

  • Subaru WRX 2015+
  • Subaru Forester XT 2014-2018

Ready to keep your Subaru running smoothly? The Radium Engineering AOS-R Kit is the perfect addition to your setup!

Proposition 65

WARNING: Cancer and Reproductive Harm
https://www.P65Warnings.ca.gov

Vehicle
2004-2008
Subaru Forester XT
2015-2022
Subaru WRX

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Who is Radium Engineering?

Radium Engineering is a company that was founded in 2010. The company specializes in designing and producing some of the best aftermarket products in the market. They have produced parts used by various racers and motorsport enthusiasts worldwide. Today, they have established a name for themselves and have become a brand synonymous with performance.

Quality in Every Product

All of their products are done in house, from research and development, design and manufacturing. They use the latest computer simulation and modeling tools that allow them to create an accurate and precise model. After all is done, they subject their products to an extensive testing procedure to ensure that it is safe to use and performs the way it is designed to.

Not Your Ordinary Stock Parts

The company focuses on manufacturing race-oriented parts and accessories such as surge tank lines and PCV oil catch can systems. They also offer fuel fittings, fuel manifolds, pumps, and fuel regulators designed for high performance applications. All their parts are made out of high quality materials that can withstand extreme forces. 

Purchase Radium Engineering Products At Vivid Racing

If you are in search of a high quality fuel system component for your vehicle, then Radium Engineering is the brand for you. Specifically made for high-performance applications, they are the trusted brand of top racers from different racing disciplines everywhere. To know more about Radium Engineering, visit Vivid Racing and check out their list of products that fit your specific needs.




Warranty

All Radium Engineering brand products are subject to a 1 Year Limited Warranty from the date of original purchase. If a product fails, it will be repaired or replaced at Radium Engineering's option when it has been determined by Radium Engineering to have failed due to defects in materials or workmanship. Warranty claims must be made by the original purchaser. If the purchase was made from a retailer other than radiumauto.com, please contact the place of purchase for further assistance.

This warranty is limited to repair or replacement of the merchandise only and shall not, in no event, exceed the original purchase price. Radium Engineering will not be held responsible for secondary or consequential damages or costs (including labor, towing, etc.) incurred due to failure of this product. Standard ground shipping is used for all warranty transactions. Expedited shipping is available, but the cost difference must be paid by the end user in advance of the shipment.

Warranty claims must ship pre-paid to Radium Engineering for review. Claims must include the failed part(s), RMA number, and original proof of purchase. If the claim is missing any of these items, it may be rejected and returned to sender. Product must be received by Radium Engineering within 14 days of RMA's issue date. Please note that before Radium Engineering can issue an RMA for any product, it is first necessary for the installer or end user to contact info@radiumauto.com to discuss the problem. Most issues can be resolved via email. Under no circumstances should a product be returned or a RMA requested before the above process transpires.

This warranty applies to the original purchaser only and is non-transferable. Improper use, installation, modification, abuse, or unauthorized repairs or alterations voids this warranty. Credit for defective products will be issued pending inspection by Radium Engineering. This warranty does not extend to third party products often used in Radium Engineering products, such as fuel pumps, turbochargers, or any other non-Radium Engineering brand products.

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