I really don't want to screw up when buying my new wheels so im trying to calcuate which offsets would be acceptable. The 17 inch wheel i want has a +40mm offset but im not sure if that will work cuz im using 215x45x17 tires. I want to use this offset calculator http://toy4two.home.mindspring.com/offset.html but i don't know the width or offset of my 14 inch steelies. Can anyone help me out?