J&L 13-14 Ford Focus ST Rear Oil Separator 3.0 - Clear AnodizedDuring the process of venting crankcase pressure back through your intake track, large amounts of oil, in the form of vapors can gather accumulate in your intake tube, intake manifold runners and even dilute your gas, lowering its octane level. This happens on all engines and is even worse with forced inducted vehicles (supercharged and turbocharged) as crankcase pressures are increased. To combat this, we have developed an oil separator of our own