Why adjust camber

The rear brakes will have less effect and will lock up the rear wheels with more ease, so a brake biased valve is advised for front wheel drive cars with negative camber at the rear. Tyre life is also reduced due to the small contact patch.

Having negative camber on the rear wheels on a circuit car will allow the car to roll onto the contact patch and generate maximum grip during cornering. On the rear wheels you can run more negative camber than on the fronts as the tyre is not needed to transmit power to the ground. Therefore, a stiffer rear end can be used with more negative camber to utilise the roll during cornering to full effect and get the maximum grip from the rear tyres; which allows the car to enter corners at higher speed and carry the speed through with the increased rear grip.

Rear ends have been seen so stiff on front wheel drive cars that they lift the inside wheel. In these cases large amounts of negative camber are used due to the high amount of roll onto the contact patch. Positive camber would increase the acceleration and top speed of the car as well due to the reduced contact patch similar to negative camber.

The braking effects are also reduced and tyre life decreased in similar ways to negative camber. However, positive camber has far less dynamic benefits. Having positive camber at the rear wheels of a front wheel drive car would reduce the grip when cornering drastically and would get increasingly worse through the first section of the corner as the car settles in to the bend.

This is due to the car rolling onto the outside wheel and lifting the inside of the tyre. As positive camber is set statically with the inside of the tyre lifted, the effects would get worse and the contact patch would further decrease. This would result in the car oversteering in the corner and slowing down a lot. The only scenario where positive camber would work at the rear wheels is if the car had a very soft suspension set up with a lot of negative camber gain. That way the car would reduce the positive camber towards neutral for the soft suspension to utilise the full contact patch of the tyre in the corner.

This would only really be seen in rallying where road cars have been modified to race. Running neutral camber on the rear wheels would decrease acceleration and top speed in a straight line due to the full contact patch being in contact with the ground generating the maximum rolling resistance and drag.

However, the braking force would be able to be larger therefore, allowing the brakes to be applied later without locking up the rear wheels as easily. Also, the tyre life would be increased due to the full amount of tread distributing the cars weight. Having neutral, or zero, camber at the rear wheels of a front wheel drive car would reduce the cornering grip of a stiff circuit car. This would be because the mass transfer during cornering would roll the car onto the outside wheel and raise the inside of the tyre, reducing the contact patch.

Therefore, the rear wheels have more grip potential in a straight line than in the corners; which for the non-driven wheels of the car would impact on performance and cause the car to start oversteering. However, a more neutral set up is often used in very wet or icy conditions where the cornering forces are reduced and suspension set ups are softened due to the lack of grip in the corners.

Therefore the mass transfer is reduced and the amount of roll onto the contact patch is reduced. At this point, having a more neutral set up will benefit the cornering grip giving more cornering speed and stability in the wet conditions.

Negative camber on the front wheels of a rear wheel drive car is the most common set up to have. The set up can range from Running negative camber will increase the acceleration and top speed of the car. This is due to the front wheel not being driven, therefore having negative camber will reduce the contact patch size in a straight line and reduce the rolling resistance of the car; allowing it to accelerate and hit a higher top speed. However, the negative camber can reduce the braking efficiency of the car due to the braking force going through less of a contact patch.

Tyre life is also reduced. The dynamic effect of running negative camber is that during cornering, a car with a stiff set up will roll onto the outside tyre. Therefore, the car will roll onto the outside wheel and onto a flat contact patch through the corner.

This increases the front end grip of the car and reduces understeer. This rolling effect occurs the stiffer the setup of the car is. The suspension set up needs to be stiff in order for the chassis of the car to roll onto a tyre instead of just moving the damper and staying level.

Positive camber on the front wheels of a rear wheel drive car is extremely rare. The positive camber would increase the acceleration and top speed of the car due to the reduced contact patch much the same as negative camber would. The braking efficiency would also be reduced due to the lack of contact patch. However, if the front suspension was soft, and the front suspension had a lot of camber gain, then the positive camber could turn to neutral camber under braking when the front of the car squats.

This would increase the contact patch and improve braking. However, the dynamic effects would over shadow this one rare advantage. Tyre life is reduced with positive camber. Running positive camber on the front wheels becomes a problem when cornering quickly, particularly with a stiff set up. As the contact patch is already reduced, turn in would have less front end grip.

As the car settled into the corner more, the grip would reduce. This is because the mass of the car would cause the chassis to roll onto the outside tyre. This would increase the positive camber of the tyre and reduce the contact patch further and further. This would result in severe understeer and is not recommended to use. One of the rare environments where positive camber is used on the front wheels is within oval racing such as NASCAR for reasons explained in the Motorsport Applications section.

Neutral or zero camber would decrease the acceleration and top speed of the car in a straight line. This is because the full contact patch of the tyre is in contact with the ground in a straight line.

Therefore, the maximum amount of rolling resistance is present from the tyre at a time where the grip is not required. However, having neutral camber is good for tyre life and braking conditions. Due to this, it is a common set up on road car applications. The dynamic effects of neutral camber depend on the set up of the car. If the car has a soft set up and zero camber gain then it would increase front end grip. Generally, in most motorsports with a stiff set up, neutral camber will decrease cornering grip.

This is due to the car rolling onto the contact patch during cornering. If it is neutral then it will roll into a positive set up lifting the inside of the tyre and reducing grip and giving the car understeer. Neutral camber is also often almost run in wet conditions in most motorsports, due to the grip level being reduced and softer suspension set up being used. Camber is the angle or tilt of the tire viewed from the front or rear of the vehicle.

A vehicle's camber affects tire wear and stability. The camber angle is measured in degrees. A zero camber setting is best for going in a straight line. A negative camber angle will result in tire wear on the inside of the tire. This occurs when negative camber wheels naturally propel the vehicle towards its midline.

If one tire loses grip the vehicle is pushed by the other tire towards the tire with the lost grip, leading to unintentional turning. Excessive negative camber can cause the wheels to tramline, or follow cracks in the road. It also worsens acceleration and braking in a straight line.

The vehicle is often too sensitive to the crown of the road curvature designed for water drainage to the sides of the road. Performance cars need increased stability when turning, as turns are done at much higher speeds than normal. When the contact patch of the tire on the road is as large as possible during the turn, the wheels grab and hold onto the road better.

Static negative camber increases the contact patch on the outside front tire during a turn which increases grip and speed of turning. This offsets the tendency of the outside front tire to roll onto its outer edge positive camber because of body roll during the turn, which would reduce grip by decreasing the contact patch size.

In fact, NASCAR drivers always turn left driving a counter-clockwise loop , so their cars have negative camber on the right wheels and positive camber on the left wheels. This is terrible for driving straight but perfect for their type of racing! Negative camber increases the tire wear under normal driving conditions, usually with mostly straight driving.

However, performance drivers do not need to replace their performance tires as often when doing a lot of cornering since negative camber decreases the relative tire wear under these conditions. Related: 5 Reasons for Inner Tire Wear. For example, if the front wheels are at Excessive camber either way will cause excessive and abnormal tire wear. Negative camber wears the inside edge of the tire, while positive camber wears the outside edge of the tire.

As mentioned, camber angles are set to balance traction and wear. Camber may need to be adjusted if your usage scenario demands better cornering performance. Abnormal tire wear, pulling, or poor directional stability may also stem from camber angle problems. Of course, we left out tuner cars and Bosozoku cars, which may feature custom lowered suspensions and extreme camber angles.

Usually, camber is only measured as part of a four-wheel alignment. Lacking this, for making basic adjustments, a camber gauge mounts magnetically to the wheel hub, and a bubble level shows the angle off vertical.

There are several methods to adjust camber, depending on the vehicle and its suspension. Stock suspensions may feature cam bolts, eccentric washer bolts, turn-buckle joints, or shim adjustments. Cam bolts and eccentric washer bolts are similar, in that the off-center bolt can be used to push or pull the suspension component in or out. On double-wishbone and multi-link independent suspensions, these may be used to move the upper or lower control arms.

On McPherson strut suspensions, they may be used to adjust the lower control arm or the steering knuckle. Turn-buckle joints are usually limited to rear multi-link suspensions but are sometimes found on front wishbone suspensions.