Improving my 2-foot vertical.
I can dunk with a 1-footed take off and have been able to do so on and off (depending on how frequently I have been playing over a stretch of time) for about 3 years. On a good day I can get in a 2-handed dunk. One thing I have noticed though is that over time, even when my 1-footed take off has been improving my 2-footed takeoff has plateaued a very long time ago (except for 1 stretch of time). Before I could even dunk off of 1 foot I have been able to grab the rim with a 2-footed takeoff, but as my 1-footed takeoff improved more and more, even to the point where I was dunking easily, my 2-footed vertical remained the same.
Now I believe that the reason for this is because 2-footed jumping relies mostly on strength and I basically never hit the weight room, whereas the 1-footed takeoff is more influenced by my plyometric ability which improved as I kept playing basketball, a naturally plyometric sport. So I want to know, as a weight room beginner, what exercises should I do (I heard squats and dead-lifts are the best for this), and how do I ensure that I am doing these exercises with proper technique? Also, right now my standing reach is about 8'1", and on a good day I can grab rim with both my hands (and get 1 hand probably 4-5 inches over the rim, so that would put my 2-foot vertical at around 27 inches). Based on my current stats, how much time in the weight room would you guys say it would take to start dunking off of 2 feet?
Another very odd thing is that I've actually dunked it off of 2-feet before. About a year ago I focused solely on jumping off of 2-feet while playing basketball, still without any weight training. Basically what I did was, when driving to the hole in situations where I would usually do a 1-2 step I did a gather into a 2-footed takeoff instead. Also, when there was any dead ball I would jump and grab the rim off of 2 feet as many times as I could attempt. This actually worked out to the point where I somehow caught a perfectly placed alley and threw it down. Also at my 2-footed peak I managed to get my entire right wrist over the rim. The odd thing about this is that even after I attempted to dunk immediately after getting my entire wrist over the rim I didn't even come close (I got rim stuffed).
To me, being at least close to dunking is when you attempt to dunk it and the ball hits parts of the top or inside of the rim while you are still able to grab the rim afterwards. I haven't even been close, and I never ever came close to a dunk off of the dribble with a 2-footed takeoff, even in my prime. Then I took a break (2-3 weeks) from playing basketball and my 2-footed vertical has never been near that level again. Is the reason that I could never come close to a dunk attempt with the ball, even after getting my entire wrist over the rim because of my technique? If so, how can I improve it?