Fresh air would be drawn through the breather tank and down through each valve ... since there wasn't a way—vacuum pump aside—to draw the vapors from the engine. It did however, have the ...

You most likely know that fuel tanks need ventilation in order to allow the fuel to continue to pump ... a vacuum. This can either be through the gas cap itself, or via some sort of breather ...

This vacuum ensures no more issues with ... a continuous supply of engine oil back to the pump. Finally, ARE also includes its breather tank and remote filter mount setup in the kit.