Well, IMO your main problem is the tire size ... you have very short sidewalls, those tires would be almost 2 inches smaller in rolling diameter than the originals ... not a very good combo for ride quality. Also, are you sure about the springs you have ?? I've never seen a listing in the Eibach catalogue for anything other than the 1.5" drop Pro-Kit for our cars ... the Sportline springs are only sold for a few very popular cars like Civics, Mustangs, etc. If you do have a 2 inch suspension drop, plus almost another full inch from the change in tire diameter, I'd say that the car is likely very close to the end of the suspension travel while sitting at ride height, and the shocks are bottoming out too easily. What are using for shocks ? If they are still the original Tokicos, or something else that's low-dollar, consider a set of Koni or Bilstein shocks all around.
cheers
Ed Nicholson
SCCoO