Breather Components

• PCV baffles and top plates: Radium Engineering PCV Baffle (with or without fittings) for Ford EcoBoost / Mazda MZR, and the APR PCV Top Plate for Audi / Volkswagen 2.0T EA888.3.
• PCV valves, bypasses and delete fittings: the Radium Engineering Adjustable PCV Valve (universal, 10AN ORB), the PCV Valve Bypass for GM LT4 / LT5, and the PCV Delete Fitting for Subaru WRX (VA), Subaru BRZ (ZC6) and Toyota 86 (ZN6).
• Oil filler caps: JUN AUTO for Honda Civic Type R (FK8/FL5), LEYO Billet Oil Cap for Volkswagen Golf (Mk7 / Mk7.5), Audi A4 (B9) and RS Q3 (F3), and Radium Engineering oil caps and baffled oil cap VTA / VTE kits for GM LS / LT engines.
• Hoses, return kits and block-off plates: the PERRIN PCV Hose for Subaru WRX (VAG/VBH/VNH), the Radium Engineering AOS-R Air Oil Separator Return Kit for Subaru WRX (GR/GV), WRX STI (VA) and Forester XT (SH), and the APR Catch Can Block Off Plate for Audi A3 Quattro (8P) 2.0T EA113.
• Breather filters and adapters: the Radium Engineering Air Filter (universal, 0.75" ID) and the 12AN Female to Air Filter Breather Adapter.

For complete oil separation systems, see Air Oil Separators and Catch Cans. Related oiling parts are in Oil Filters, Oil Coolers and Oil Pumps and Sumps. You can also browse all brands.

Most breather parts are specific to an engine or chassis, so start with your vehicle's identifiers:

• Engine code: for example EA888.3 or EA113 (Audi / Volkswagen 2.0T), EcoBoost / MZR (Ford / Mazda), or LS / LT4 / LT5 (GM).
• Chassis code: for example FK8 or FL5 (Civic Type R), VA (WRX / WRX STI), ZC6 (BRZ), ZN6 (Toyota 86), Mk7 / Mk7.5 (Golf), B9 (A4) or 8P (A3).
• Fitting sizes for universal parts: check thread and hose sizes such as 10AN ORB, 12AN female, 3/8 BSPT to 10AN male, or a 0.75" inside-diameter filter so the part matches your existing lines and ports.
• With or without fittings: some parts, such as the Radium PCV Baffle, come in versions with or without fittings. Choose the version that matches the hardware you already have.

Check each product page for any fitment conditions before ordering.

Installation by a professional is recommended. Breather parts connect to the crankcase and intake, so poor sealing or incorrect routing can cause oil leaks or affect how the engine runs.

Depending on the part, you may also need hoses, AN fittings or a catch can or air oil separator to complete the system. See each product page for kit contents.

Changing or removing PCV components can affect emissions equipment. Confirm that any modification suits your vehicle's registration requirements.

What does a breather component do?
It is part of the crankcase ventilation system. These parts control how crankcase gases and oil vapour are vented or returned to the engine.

Are these parts vehicle-specific?
Many are made for specific engines or chassis codes. Some Radium Engineering filters, valves and adapters are universal and are sized by fitting type.

Which brands do you stock?
This collection includes Radium Engineering, APR, PERRIN, JUN AUTO and LEYO.

Do I need a catch can as well?
It depends on your setup. Some parts, such as block-off plates and return kits, are designed to work with a catch can or air oil separator.