The DID is actually the only one I can close with a screw. Its just that at 20 watts, closing the fill hole is usually not an option.
The good thing is that the FC is already able to sustain a 20 watt setup with a closed fill hole (which is already a wow factor) but it produces less vapor. If I can't eat the whole cake I'll just go back to a 1ohm setup...
I've seen ppl building really angry coils on Nextel, that may be an option too...
the lowest coil I have is a 28g at 0.7 on mechanical, this one is the ac-9 & vela, fill hole open. it performs really well, not sure if I were to close it up.
