LOL let me have another cup of tea and think before I speak.
My initial question was, would changing that particular oring to a smaller one have any impact on the airflow. So I am with you on the fix.
Ok, one last post before I turn in. Sure, but it will be in a negative way. If air can seep in around the o-ring, juice could slip out (and into your BB). Plus it would be bypassing the carto, reducing vapor. Sounds like you may need to try a different carto, as I am agreement that airflow is poor on a standard carto. Some people like it and some don't. The IKanvape cartos seem to have more airflow, but not sure you can get them where you live. So the other suggestions would be Billet Bridge, Diver, Sophia, Sabot or a build it yourself rba.
Anyway, gotta run.....4am comes to damn quick.


