Killer B Motorsport Air Oil Separator w/ Plumbing 2002-2007 WRX / 2004-2007 STI / 2004-2008 Forester XT

After years of being asked to develop a Killer B Motorsport Air/Oil Separator, we are proud to announce we have released the GD Air/Oil Separator. This is a product weve been asked to develop for many years, and in that time there has been a lot of research, engineering, simulations, development, testing (and repeat), with several Subaru engines and build types. This has been going on over many seasons, exposing to environmental extremes, and driving conditions (daily driving, auto-X, drag racing, dyno testing, etc.), as well as on stock engines and exceeding 700whp.

The goal of this product is simple. To function as its Air/Oil Separator description implies: the removal of oil, in liquid or vapor form, from the vented crankcase gasses. Simple in premise, but function wise theres a bit more to it. Varying oil droplet sizes, with differing pressure and velocity conditions. Different engines with varying venting characteristics or a street car vs a track or performance elevated engine. The variable list goes on, making acceptable function and performance a difficult challenge.

Performance must be spot on, but the effect on the engines operation must be unchanged at the least, or improved ad best. We prefer the later. This is accomplished by using a design that has no restrictions; media or baffles, to reduce the flow potential of the crankcase and head vents. Under positive boost conditions it will produce vacuum in the crankcase. The benefit of this is improved evacuation of crankcase gasses and the many other benefits that can be had with crankcase vacuum; improved ring seal, reduced oil consumption and improved power potential.