Regardless of spring rate you should not be experiencing a bouncy ride.
Since you have higher rate springs, your struts will have to be adjusted to a higher dampening level to control the movement of the higher rate spring. Try turning up the strut settings, if the shocks are able to handle that spring rate, you should notice the ride getting smoother and less bouncy. That will be your optimum setting for racing and street.
Your struts are designed to dampen spring motion not make the ride stiffer or softer.
I have heard people complain that the Teins are poor/bouncy before. Hope you get it to your liking. If not I would suggest selling these to someone less performance oriented and buying a superior damper such as Koni.
Dudeman