Camber Camber is the angle of the wheel versus true perpendicular, and is measured in degrees. Camber can be expressed as zero degrees, in which case the wheel is exactly 90 degrees perpendicular to the road surface, or as a positive or negative value in degrees. Positive camber is when the distance between the centre to centre of the top of the wheels is greater than the centre to centre distance of the bottom of the wheels. Sounds confusing, but if you imagine a bow-legged person, you would be able to visualize what is meant by positive camber.
Negative camber is the other way around, much like a knock-kneed person.
The effect of positive camber is outer shoulder wear on the tyres, while the effect of negative camber is inner tyre wear. This pretty much suggests that the ideal camber should be zero, but in real life, this is not so. The car is dynamic, and the cornering forces acting on the outside of the tyres tend to sweep the tyre under and into the inside of the car, thus accentuating the outside shoulder wear. Thus it stands to reason that for some cars, it is necessary to build in some negative camber to reduce this outside shoulder wear. Unfortunately, most cars today do not have built in camber adjustments.