What are good springs for the rear?

What length shocks and what rates make good springs for the rear?
My rear shocks are an inch shorter than the front s and i've had to fit harder springs than i would have liked to stop them bottoming out.

How heavy are you and have you got a lot of fillings? Mine are 180s but if you are racing you might want to go harder. Live axle or independent could affect your thinking as well.

yours, Pete.