Trying to understand something about car dynamics

Hi
There is a "phenomenon" that on 4-6 gear curves, I "throw" my car into the apex with a lot of steering, I get very good turn in, let's say 1 lateral g for 0.5 second, and then I get more like 0.5 lateral g with heavy understeer for the rest of the turn. It will happen especially when I'm trying to get through the corner on full throttle (coming from a slow corner before) , I'm not talking about simple power understeer (if this is the term for rwd).
Does this phenomenon has a name ? And also , I thought it might be too much negative toe, the description says it gives a good turn in but less mid-turn grip. I also thought it might be the low default tire pressure causes the tire to twitch too much, or maybe too soft\hard suspension causes this with weight transfer giving me sudden loss of traction ?
I would of course try my ideas if it was easy but I'm having real hard time to get this to happen to me on purpose.
Thanks - I hope you can understand what I mean, if not I will try to record.

 

To put simply, what you are describing is under steer caused by lack of down force and/or too little negative camber. You make your initial turn, the tires start to roll over and make full contact with the ground. As you continue to keep the throttle wide open the tire starts to roll over itself putting less and less rubber on the ground. Part of it could just be going too fast into the corner also.