From an experience I had with mine last night, I can almost guarantee that the over-tight draw you're describing is causing extra juice to come in the hole from the tank, moving up the carto and spilling down the center tube. I've done it too many times to count. Try backing it off 1/4 turn and see if the draw gets better after getting rid of the excess juice (no, there really isn't any good way to do this, lol).
From what I've read, most flooding problems are due to pressure rather than hole size. If you're creating a vacuum (tight draw), more liquid is going to enter the carto than should, even if the hole is very small. A little bit of vacuum on draw is a good thing, keeps the carto moist, but too much will definitely flood it.
Also, when filling, make sure you're letting all air escape from the tank before sliding the carto through the gaskets...if there's pressure on the tank end it will flood as well. If the tank is functioning properly the only time juice will really be transferred into the carto will be on draw.
And I guess another edit is in order. I did this video, shameless plug:
Anyway, I did this video right before going to bed. In the morning, ALL of the remaining liquid in the tank had drained out onto the paper towel I set up on my desk. I had overfilled the tank, and didn't allow enough time to let the liquid soak up into the carto before I sealed it. After sealing it, it just kept draining at it's initial rate because it was creating its own vacuum as it flooded the center hole in the carto and flowed down. Just be gentle with it and patient...I was in a hurry and lost a decent chunk of juice because I wasn't careful with it. Vaping definitely has a lot of conveniences in comparison to smoking...but man, I never lost a pack of smokes because it leaked all over the place. I'm putting this down to new things requiring practice.
OH, and I just picked up some Smoktech 1.7ohm Single Coil XL cartos, and definitely prefer them to the 1.5 DC. Slotting them myself so I don't have the convenience of the little bib that keeps the tank from sliding off the bottom, but I can adjust hole size for some thicker juices. My DC carto stopped firing "sometimes" on my KGO about a week after I started using it, sometimes cleaning the threads would help it, sometimes not. It died altogether on me yesterday. For a 3.7v device, I'd say stay away from the dual coils...they just haven't worked well for me. When my ProVari comes in, who knows what my opinion will be.
. What you are saying about the vacuum makes a lot of sense, I was thinking something along the same lines myself at one point. I am a pretty simple dude though and this is just too much work for too little outcome. Ya know? So I have switched back to my standard EGO tank set-up and am vaping happily. I also have a Provari in the mail on the way to me, maybe Ill try out one of those SS Lil mama tanks I think they are called? quite expensive but have heard great things! And as the dual coil as well, I think unless your very particular on the warmer vape, is not necessary. Though I am very open to suggestions for VV with them, I don't know too much about that world. I've got some boge 3.0's coming at the same time as my Provari. I hear they are quite deliciously......functionable. lol.
