Camber Explained: Static Angle, Camber Gain, and the Contact Patch
Camber is the lean of the wheel when you look at the car from the front or rear. Negative camber means the top of the wheel leans in toward the car; positive means it leans out. It is the alignment setting people notice first, and the one most often chosen for looks — but its job is to control how the tire meets the road while the car is cornering.
Why negative camber helps in a corner
In a turn the body rolls outward and takes the wheels with it. On the loaded outside tire that roll tips the top of the wheel outward, lifting the inner edge of the tread. Starting with some negative camber cancels part of that, so the outside tire sits flatter at the moment it is doing the most work. The tire's carcass also deforms under side load, which asks for a little more negative camber still.
The trade is straight-line behavior. A tire leaning in runs on its inner shoulder when the car is upright, which reduces the contact patch for braking and acceleration and concentrates wear on the inside edge.
Static camber is only the starting point
The number on an alignment sheet is static camber: the car sitting still at ride height. What the tire sees in a corner is that number plus everything the suspension does as it moves.
- Camber gain — how much camber the suspension adds as the wheel moves up. A double-wishbone layout with a shorter upper arm gains negative camber in compression. A MacPherson strut gains little, and can start losing it once the lower arm passes horizontal — a common result of lowering.
- Steering — caster adds negative camber to the outside front wheel as it is steered.
- Body roll — each degree of roll takes close to a degree of camber away from the outside wheel, less whatever the suspension gains back.
That is why strut cars are usually given more static negative camber than double-wishbone cars for the same use: they recover less of it in roll.
Camber and the fender
Camber rotates the wheel about a point near the contact patch, so the top of the tire moves sideways much more than the bottom does. The movement at any height is simple trigonometry.
| Added negative camber | 620mm tire | 660mm tire |
|---|---|---|
| 1° | 11mm | 12mm |
| 2° | 22mm | 23mm |
| 3° | 32mm | 35mm |
Those figures are at the very top of the tread. The fender lip usually sits lower than that, so the gain right at the lip is smaller, and depends on ride height. This is the mechanism behind running a lower offset with more camber: the wheel sits further out at the hub while the top of the tire is pulled back under the arch. See poke and tuck for the rest of that calculation. How the camber is added matters as well — an adjustable upper arm or top mount moves the top of the wheel in, while a longer lower arm pushes the bottom out, and the two leave the tire in different places.
Wear and what is "too much"
Camber on its own wears a tire slowly. The fast inner-edge wear people blame on camber is usually camber combined with toe: a cambered tire that is also toed is dragged sideways on its inner shoulder for every mile. Lowering a car often changes both at once, which is why an alignment after any ride-height change matters more than the camber number itself.