I too am interested in modifications that could make the VB2 put out more vapor than stock setup, understand there will be trade offs when making mods and am willing to take the good with the bad given I like having options for different situations and occasions.
Below are a few pictures of what I've been playing with for the past week.
The steel mesh screen on the far right is the one I place directly over the vapor tube (the brush on left effortlessly cleans VB2/VXC/EQ baskets, Pax and regular screens).
Here's that screen (on the far right in the above picture) inserted flat into the bottom of the VB2's heating chamber:
Loaded .1g of girl scout cookies directly on top of the screen:
Then insert the VB2 basket the normal way so as to tamp down the load and keep it sandwiched between the screen top and the VB2 basket bottom.
After the basket has been inserted the end-cap gets screwed on. Note that the stir-pin will be jammed/pressed up against the VB2 basket floor after the end-cap is screwed on - I make sure to not twist the stir-cap mechanism to avoid putting unnecessary pressure on the stir-pin and basket floor.
Once end-cap is screwed on, I set the unit to heat level 1, let it get to temperature and go. If unit's battery level is at 3 or less blue bars then I start with heat level 2. (It shouldn't make a difference and i may be imagining it entirely however my observations so far have been that battery level does seem to result in a noticeable ABV shade difference, more testing required here. With the VB2 battery fully charged, heat setting 3 would make some very dark ABV - must be careful as i suspect higher heat settings may cause herb to combust with this mod. Then when VB2 battery level was low at 1 or 2 blue bars then heat setting 3 would generate lighter ABV at the end of the session with same duration, something to keep in mind.)
That honeybun type tool really comes in handy for emptying the chamber afterwards.
Below is duff from .1g of cookies after a 6 minute session at heat level 1 (with mod loaded VB2 fully charged):
Below is duff from another .1g load of cookies, 8 minute session at heat level 2 (with mod loaded VB2 fully charged):
Here is my AVB from 4 separate 12 minute sessions with .1g GSC loaded in each. Pax at medium heat setting, Solo at 4 heat setting, fully charged VB2 load mod at heat setting 3, as well as fully charged VB2 stock basket loaded at heat setting 3.
Thanks for trying the experiment and your feedback Jared, I really appreciate it. It is great to read that the change/hack had good results for you too. Now the VB2 can get me where I like to be with one quick high-temp session with just .1g of herb, actually works well up to .15 when sharing with a friend may need to load a 2nd time. With load sizes larger than .15g, the basket sits raised even more to the point where the stir-pin starts to dig into the basket floor. Also I think the compressed herb over the vapor tube results in a more restrictive draw and quicker loss of flavor versus stock setup, however the KO hits it delivers in short order make up for it when that's what the occasion calls for. I don't mind the conduction herb roasting action as solo sessions are over quickly, since herb stays a flat disc shape stirring doesn't seem critical.
I'll keep testing away, last tests were with VXC ELB top-cap used in place of the VB2 basket to accommodate .2g loads, all worked well in sharing situation where my burner buddy and I were significantly vaked after a 10 min session. The VXC ELB top cap accommodates the stir-pin while taking up less volume than the VB2 basket therefore more herb can be loaded into the heating chamber, and the extra herb should ideally be packed to touch the upper side wall surface of the chamber. That said, I try to use the Pax for portable sessions when larger load sizes are desired.
