Holmz, I think you and Jacob are saying the same thing about rebound.
What do you mean when you say the rear becomes unglued in high speed transitions? Is it too slow to transition from one side to the other and then snaps loose? Do you see this effect in long high speed sweepers or only in transition?
Going through a solemn, the rear will stay under control for about two turns. After that, the next turn, the rear will break traction and start to slide thus broadsiding the cone. When the sway bar is stiffer, it appears that the bar helps hold weight on the inside rear tire. Thus, you can carry very high speeds through the solemn.
When traversing a sweeper, the rear feels as if it wants to break loose with the bar in the softer setting. The same feeling is present on high speed sweepers on a road race courses and causes you to not maintain acceleration.
Before stiffening the front bar, I started to dial out rear rebound and this helped. The problem is that the shocks are missing the valving to separate compression from rebound. So, as I dial out rebound I loose the nose of the compression at low speed. This is going to get corrected, they just did not have the needles the last time I had the shocks off.
My feeling is that the car likes the softer roll stiffness of the front but lacks rear roll stiffness. Normally, I would fix this by working with a rear bar. Forward traction is extremely good to the point that it is difficult to break traction when coming out of a corner. The thought was maybe the car has too much bump steer in the rear but after looking at the geometry, I do not believe this is the case. The rear toe links have been upgraded to Sector 111's setup.
Before changing from the stock springs, the sway bar was run at the current stiffer setting. After shooting some video of the suspension travels, it was noted that the car would carry the inside front while exiting the corners without picking up a push. The car was also fairly stable through the solemns. Also, the comment about 3 degs being too much rear camber was put to rest after watching the outside rear tire on a sweeper. It flattened the tire and you could see the distortion of the side wall.
I am sure I can find a way to soften the behavior of the car but I would rather do this without hurting the other end. That is why I am asking for suggestions because I am not that familiar with setting up a mid engine car. My experience is with front engine, rear wheel drive.