I recently did an extraction with some Black Caapi vine (Trueno).
It really surprised me, from 500grams I yielded 2 grams of Alkaloids.
Bearing in mind that this was some large old vine I thought maybe it should have more alkaloids within.
The picture below is a piece of the vine 500g in weight, I bashed it several times with a hammer before I realised that it would need to be cut up into smaller pieces first.
So I've saved it for later and I used some smaller bits.

I took a gram of the Alks and infused it with a gram of spice onto 1.5 grams of the Trueno vine.
Basically it doesn't work..
Some Changa mixes just don't really do anything apart from slight DMT effects.
Like Mugwort changa or my newly tested Clitoria Ternatea changa , there are more that for some reason really struggle to work.
Either way the Trueno is a fail, but I wont give up on it, ill smoke some more tonight.
The yellow Caapi changa, you only have to look at it and it hits you like a ton of bricks.

Edit.update :Ok it does work , its a different animal so to speak, deeper and darker.