Tried to wire also the positive side directly to the battery and battery went from 14 to 14.20! But that way I'm canceling the fuse(that I burned two in the process &#128516! (Or I can just mount on more at the extra wiring somehow). Still waiting for the new rectifier to see if I'll have better results.

 

Ok now the (cheap ****)rectifier is here, I tried it, have slightly better voltage 14.1 but this is stable at all rpms! So I'm thinking to keep this one, and connect also the + from the rectifier directly to the battery, with a fuse in between. I'll have 14.2-14.3 I guess and this is exactly the lower limit it should have.