During everyday engine operation, blow-by gases, as well as oil vapor from the engines rotating assembly, pass through the PCV valve and are routed into the intake for the engine to burn off. Before ever making it into the cylinders, some of that oil mist and other contaminates adhere to the backside of the hot intake valves. Over time a thick crust forms significantly reducing performance and potentially leading to a costly cleaning or repair. This is especially a problem for the 2.0L motor because there's no fuel (Direct Injection) passing over the valves to wash and keep them clean. This is why an OCC is a must have for the Ford Focus ST.As the PCV gases enter the catch can a pressure drop occurs. The oil then begins to fall out of suspension as it flows through a series of 3 perforated filter plates. As the gases flow through the plates, the oil sticks and the gas is all that reaches the outlet at the top of the catch can. Oil that accumulates on the filter plates runs off and is collected in the bottom where a large 5/8" quick drain makes emptying the catch can a breeze.Throughout the life of the catch can, the perforated filter plates will never break down or need to be replaced like catch cans with screens and mesh filter material.What's wrong with the OEM PCV valve?The short answer is nothing as long as the car is stock and everything is properly maintained. But, if you are running anything more than stock boost or would prefer to not have oily residue in your intake and crud building up on your valves, read on.Because the PCV valve is the heart of the PCV system, let's stake a minute to discuss it. This thing is notorious for not being able to completely close to prevent boost from entering the crankcase, even when brand new. Add a few thousand miles worth of crud flowing back and forth through and the worse it gets. And the more boost you run, the greater the problem becomes.The optional check valve kit is designed to be closed 100% of the time unless vacuum is present. This check valve is oil, fuel and chemical resistant. It's constructed from brass, it has an incredibly low crack pressure and it's properly sized so that normal flow isn't affected.Unfortunately, the OEM check valve just can't close instantly under boost and therefore crankcase pressure and turbo spool times are increased. For higher boosting cars or those seeking the best possible performance out of their engine, an OCC check valve is recommended.Application:- 2013 & up Ford Focus ST** Upper mounting location requires a sound symposer deleteFeatures:- Designed and Manufactured in the USA- Easily installed utilizing the supplied OEM factory fittings- Hoses cut to length and pre-assembled- Entirely constructed out of 6061 aluminum- Precision TIG welding of all components- Large 5/8" easily operated drain valveIncludes:- 1 Oil catch can- Application specific mounting brackets- Pre-assembled polyester reinforced oil, fuel and chemical resistant hose with factory fittings- Stainless hose clamps- Stainless mounting hardware- Drain Hose- Quick drain valve- Check valve (Optional)- Installation instructions are available in our support section
