How old are your front shocks? It may be the upper ball joint- is it loose? How are the bushings on the upper arm? Are the new springs stock or after market?
You may check the tie rods also (inner and outer), only because of the turning the wheel all the way to the left or right makes a grinding noise?
When you hit a bump does it sound like something mechanical is bumping around or just feels like wheel hop? Have someone drive next to you and watch your wheels when you hit some bumps- do they hop or get pushed backwards?