Just for conversations sake, here's the actual tension for a set of .009 x .046 strings on a 25.5" scale guitar:
(Source: D'Addario Strings)
E: 16.91 lbs
A: 19.04 lbs
D: 18.38 lbs
G: 14.68 lbs
B: 11.02 lbs
E: 13.14 lbs
Total: 93.17 lbs
So, the springs need to exceed this figure by at least 15% to bring the bar back to pitch...