Porsche Hastech Engineering Porsche 911 Crankcase Ventilation Oil Blow by Separator H911 106 KIT 928 341 028 37R The softer aluminum caused the Model And Year:928 (1983 1986) The softer aluminum caused the original lug bolts to deteriorate quickly making these an ideal replacement made with non corrosive Porsche Vent hose for 911 (1970 1973) models Fits all aircooled Porsche 911 models from 1965 through 1998 Features and Benefits:Reduces the oil blow by from the crank ventilationKeeps the oil in the engine while still allowing good crank ventilationVery simple mounting sandwiches between the crankcase and ventilation the lid breather coverUsed on all Hastech race & street enginesRecommended for all aircooled Porsche 911 engines to help reduce oil consumption caused by ingestion of oil laden air into the intake caused by excess crankcase windage and blow by