First off, going to make a general warning, DO NOT tighten the 510 pin to tight on the Higo!
Here is why...
That is the insulator which keeps the shoulder of the 510 pin from shorting on the shoulder of the 510 connector on the base. If you crank it down you will pinch it between two metal edges, this has the potential to cut the soft silicon insulator, and allow the 510 pin to hard short! It should be fine if you do not over tighten it.
However that is most certainly not a good situation since this same 510 pin tightens the positive post into place.
I just got done doing some modification to this beast! I thought the flavor was great before doing so, now that it is keeping the wick saturated, WOW, off the charts for flavor.
Just to test wicking after the changes I made I ran through a tank of 100VG DIY juice, chain vaped a tank @ 60 watts .5 ohm 3mm build! I know it would go much higher and keep up, very wet dense, saturated vape! I didn't go higher because the heat output was too much for me.
After that tank was gone I refilled with 20/80VG, did get just a couple drops out the bottom air flow, probably have to increase wick density just a little.
Now it was wicking previously 100VG up to 45 watts, but I could tell it would not have gone any higher. pretty much same build, cotton medium tight in the 3mm coil, wick tails thinned to about 1/3 density. Well after the changes saturation is pretty much maxed out, and about perfect. The difference in flavor is huge, even though it was good before, it just wasn't up to potential.
So what did I do? I opened 1 juice flow hole on each side to about 2.5mm, I also took a needle file and slightly enlarged all the holes for the tank feed. I will also caution here, one each side of the upper air flow slots mine has 4 of the 6 juice holes, if you were to go to large you would risk cutting into the air flow, which would ruin the atomizer.
I've also had it resting with a full tank, no flooding or leaks. I believe all four of the juice holes could be enlarged to 2.5mm without issue, may have to compensate a little with wick density though. Forgot to mention I did nothing with the flow control so it still could be adjusted with that if need be. I've removed the flow control ring completely for now.
I've also modified the poorly done 510 connection. I had a plastic insulator in my parts bin from an unknown clone RDA, it fit pretty much perfect, except I had to file the collar a bit shorter. I think they may have chosen the silicon for sealing from any seepage? Sort of makes sense. My solution to help insure against leakage was a grommet from an old pro-tank head with the ridge cut off. I don't think it would have leaked without it as it is a very tight fit, but added the grommet on the deck side just in case. A similar arrangement with factory machined parts would be perfect.
A small o-ring may be helpful if you are unable to find a hard plastic insulator. should help keep any potential for a short to a minimum.
OK, well on to the pics.
An o-ring, and a the cut off piece from donor protank head. either would be better then nothing, and was my first attempt, but wasn't happy with results.
The bright piece is the OEM insulator, darker is the hard plastic from donor RDA.
Modified 510 pin insulators, first is hard plastic piece, then Protank grommet to help seal.
510 tightened and corrected with donor RDA insulator.
From the inside after mod, perfect, and tight!
Enlarged Juice flow hole, couldn't really go any larger vertically.
Tank flow holes slightly enlarged with a jewelers needle file.
