Should you open or close the airflow?
It depends on whether you want to vape like a ninja or a steam engine. Opening the airflowproduces lots of vapor and cools the hit. Closing it concentrates the flavors, boosts the throat hit, and keeps you from draining your tank in three minutes flat.
An open airflow reduces the pressure drop inside the atomization chamber, which requires more power to vaporize the liquid. Conversely, a restricted airflow increases flavor concentration but can make the vapor uncomfortably hot if your wattage is too high for the incoming air.