Originally Posted by: Dr_simonI have 3 springs on at the moment (located into the middle 3 holes of the trem block) and I'm wondering if I should add more springs and slacken the tension on them.

That will not work. If the bridge is in balance now, you have to right amount of springs/tension.

What you should do is replace the springs(this should be done regularly). Old springs tend to do exactly what you described.