The exhaust housing is a 8cm?. Turbine housing, great for spool up while providing sufficient turbine flow to make about 470+ whp with the right combination on E85. Specs & Features: Compressor Wheel Inducer - 52.5mm Exducer - 68mm Turbine Wheel: Inducer - 55.8mm Exducer - 49.2mm Turbine Housing - 8cm Oil Feed Line Included.