first of all you need to understand caster. caster is the rearward tilt of the steering axis. the more positive you go in caster, the more the car will tend to want to go straight and the more camber is added while turning. also in theory by adding more caster you are lifting one side of the vehicle when turning increasing steering effort.
if you wanna learn more [ame="http://en.wikipedia.org/wiki/Caster_angle"]Caster angle - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Caster_angle.svg" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Caster_angle.svg/250px-Caster_angle.svg.png"@@AMEPARAM@@commons/thumb/f/f8/Caster_angle.svg/250px-Caster_angle.svg.png[/ame]