Very few people know that the tires of their car are not perfectly perpendicular to the road. Many vehicles in the 21st century have their wheels slightly slanting towards the inside of the car. When the wheels of a car are designed to lean slightly inwards or outwards, they are said to be cambered. A slight inward inclination is referred to as positive camber, and when the wheels are splayed outwards, they are said to have negative camber. The extent to which wheels are cambered depends on the function of the vehicle.
For instance, regular cars will have a very slight negative camber, while sports cars have considerably more camber.
The main reason that the wheels of a car are negatively cambered is to provide stability when the vehicle is negotiating a corner, or when the car is moving at high speeds. When negotiating a bend on the road, the vehicle’s weight is transferred to the outside wheels. Thus, the negative camber makes the tire to be flatter to the road. For this reason, the likelihood of the car to negotiate corners at high speeds influences the extent to which the car’s tires are likely to be cambered.
Why are Car Tires Cambered?
Camber refers to the angle at which a vehicle’s tire (view on Amazon) stands relative to the ground. The easiest way to determine the camber of your car’s tires is by using the anterior view of the tires when the vehicle is motionless. Usually, when the vehicle is stationary, its wheels maintain a static camber. On the other hand, when the car is in motion, especially when negotiating a corner at high speed, the body roll effect can reduce the wheels’ contact area on the road. This reduces the stability of the car, which poses the danger of having your vehicle rolling. Therefore, mechanics often adjust the camber settings of high-performance vehicles to increase the vehicles’ stability and improve the cars’ performance.
There are various reasons why the wheels of a car are cambered. Apart from increasing the wheels’ contact area with the road, the tires can be tiled inwards outwards to reduce the ground clearance of the vehicle. The bodies of cars with cambered wheels are usually closer to the ground than normal cars. However, unlike the standard vehicles motorcycles, car tires are broader and are not designed to negotiate bends at high speeds. Therefore, to counteract the body roll when going around a bend, the wheels often use a negative camber to maintain the vehicle’s stability. Whereas the camber of the wheels depends on the function of the vehicle (with the main reason being car sport), some people often increase the camber for cosmetic purposes. Some motorists enjoy attracting the attention of other motorists and pedestrians and will, therefore, increase the camber of their cars’ wheels for aesthetic reasons.
How Much Should the Tires Camber?
Often, the extent to which the tires of your car camber depends on the vehicle’s suspension setup. For instance, cars with a MacPherson struts suspension system usually have considerable negative camber. This is because these cars have only a modest gain in the camber when under compression, in comparison to regular cars. When vehicles with this suspension system get the body roll effect at corners, the standard camber is insufficient to increase the car’s stability, which compromises the safety of the occupants of the automobile.
Hence the manufacturers of such vehicles allow extra camber to negate the effects of body roll when negotiating corners at high speeds. On the other hand, cars with different lengths of A-arms and those that have multi-link suspension systems do not have this shortcoming in similar circumstances. They are designed to gain negative camber faster than those with the MacPherson struts suspension system when going around a bend.
A motorist who drives every day may consider having the camber to his/her vehicle set at -1.5 degrees for the front wheels and about -1 degrees at the rear wheels. The hind wheels are often set at less camber because they do not have to deal with the same steering load as the front wheels. For a project car, the extent of inclination increases further to values of about -2.5 degrees for the front wheels and about -1.5 degrees for the rear wheels. If you own a high-performance car, you should have an inclination of -4 degrees for the front wheels and -2 degrees for the back wheels. However, a motorist needs to determine the car’s suspension system as well as the stiffness of the spring before trying to change the camber of the vehicle.
Some car manufacturers use positive camber because of the inclination of the steering axis. This inclination is between the steering control’s arms and is controlled by the kingpin found at the center. Consequently, if the steering system’s axis is vertically perpendicular to the tires during motion, then the tire will have a large scrub area through which to rotate when the driver steers the vehicle. The scrub radius is the radius through which the tire has to turn for the wheel to complete the steering arc. Therefore, the tires are placed at a slightly positive inclination to reduce the scrub area and make steering the car more comfortable.
Why Your Wheels Are Cambered
Most vehicle owners understand that a vehicle must be inspected and serviced from time to time, as referred to as routine maintenance. For those who don’t, the likelihood of problems that cause cambered wheels is extremely high. If the vehicle is not inspected routinely, small problems can escalate to major problems that are much more expensive to fix. This is also true for vehicles which sit for long periods of time.
If you want to avoid wheel problems or other issues and save $100s of dollars that you’ll spend at the auto repair shop, you’ll need to service your vehicle often – you can use our mechanic-rated Auto Maintenance and Repair Manual to do this. It’s basically what mechanics use to go through your vehicle to check if there are any problems that need fixing. As soon as they notice the most minor problem, they’ll ask you to fork out some money even though it’s a problem you can fix yourself in minutes – the manual will teach you how to maintain your vehicle every few thousand miles and it’ll teach you how to fix minor problems that mechanics will ask you to pay for; saving you money in the long run.
A lot of our readers have the Auto Maintenance and Repair Manual printed on their garage wall and 92% of them haven’t visited the auto repair shop in the last year because they know what to do to avoid problems. All it takes is giving your vehicle a little attention every few thousand miles and you’ll never spend money at the workshop again.
Dangers of Excessive Camber on the Tires
Numerous risks come with too much camber. Some of the most common include:
- Inefficient Braking – The car tire is designed to have the contact patch always flat or almost flat, not tilted at an angle. Therefore, increasing the angle that the tire makes with the road will reduce the grip that the tire will have on the road, which makes the car take longer than usual to stop.
- Tire Wear – When the car’s tires make an angle with the road during motion, they wear out much faster than when the tires are perpendicular to the road. This is because the tires are designed to operate at acute angles, like motorcycle tires. Additionally, increasing the camber also increases the chances of getting punctures on rough roads.
- Drivetrain Wear – The steering system components and the wheel components are engineered to run efficiently at precise angles, clearances, and tolerances. When there is excessive negative camber on the wheels, these parameters are exceeded and will accelerate the wear of these components. The unnatural angles increase friction between the car’s moving parts and thus will wear out these parts of the vehicle.
- The Ride Experience – Most vehicles’ suspension systems require up travel and down travel. When the vehicles are stanced (lowered) as an effect of excessive camber on the automobile’s wheels, the up travel will be significantly diminished, which reduces the smoothness of the ride when the car is in motion.
- Reduction of Electronic Safety Aids – Many modern cars have electronic safety aids, which help to control the vehicle when the driver loses control of the car. However, these aids are designed with the regular set up of the car in mind. Altering the car’s original design by cambering the wheels will reduce the efficiency of the car’s safety aids. Thus, in instances when the driver cannot control the vehicle, the lives of the occupants of the vehicle could be in danger when the angle is too acute.
- Steering – Although the positive camber is used to improve the steering system’s performance, excessive negative tilting of the vehicle reduces the effectiveness of the steering system. It is well known in the motor world that stanced cars often struggle to reach full steering lock. The wheels will rub the guards more when the camber is excessive, and the geometry gets out of the recommended limits, hence affecting the steering performance.
After reading this piece you should understand why most tuned cars have very inclined wheels.