What poundage/spec springs for 3.0 V6 Corsa?

[ibyscorsa]

As title,

I need info on what the poundage springs I should get on my bilstein B6 dampers for the front?

I can see a lot in rallydesign but I don't have a clue what the numbers mean in the specs. All i know that "rate 400" means 400 lbs. I was thinking more about 650lbs but is it 1.9" or 2.25" I need?

Any help would be appreciated.