Roger Clark Motorsport Sump Baffle PlateNote: Not compatible with Killer B Super G oil pan Oil control is a problem which can effect the Subaru's "Flat Four Boxer" engine design more than most due to its high crank case pressure and horizontal engine design. When cornering at high speed the design of the Subaru engine means that oil can work its way out of the sump oil pan and flow across to the cylinder head castings, leaving a lower volume of oil behind surrounding the oil pick up pipe.