RB Series Oil Head Drain Kit SpecificationsNissan RB engines and in particular turbocharged versions (RB20DET RB25DET RB26DETT) often suffer from a common design fault : the ducts allowing the oil to flow naturally from the top end of the engine to the sump tank are undersized. Under intense use (high revs and high boost pressure) oil tends to accumulate in the top end of the engine often with disastrous consequences that can even lead to engine failure.Add an additional head drain kit to avoid build up and overflowing thanks to this complete kit which includes : Dash adapter for the headFitting to weld to the sump return1 meter braided lineTwo 90° Dash fittingsInstalling this kit requires some technical know-how : the head side oil output goes in place of a factory installed blanking cap (see photo) and requires drilling and threading of 2 holes. The oil return fitting will need welding to the sump tank.