wheel alignment guide
Wheel alignments are an important part of looking after a car. Not only does a wheel alignment help with the vehicle’s handling characteristics, they also help with tyre wear, fuel economy. Also, the technician can find issues with suspension components and bushes.
There are three main measurements that are checked and in most cases can be adjusted.
Camber is a measurement of the vertical axis of the position of the wheels. Measured in degrees and minutes, camber can change the characteristics of a vehicle in a big way. For example, a circuit car will have negative camber to aid with corner grip. As the car leans into the corner, the wheel will have a majority of the tyre contacting the road surface. Most factory cars will have slight negative camber from the factory to help with handling.
Castor: castor angle is the measurement of the angular difference from the vertical axis of the position of the wheels. Castor works with camber to a degree and helps with the steering wheel self-correcting, which will make a car easier to drive. Due to Australian roads camber going to the left, it always helps to have slightly more castor on the left side of the vehicle to help promote the vehicle drive straight.
[Diagram from Tenhulzen Automotive]
Toe adjustment is the main adjustment made when doing a wheel alignment. Measured in millimetres, toe is the measurement of the horizontal axis. Too much toe will increase tyre wear, toe needs to be adjusted with camber angles in consideration. For example, a street car with negative camber would not be matched with negative toe as the tyres inside edge will wear quickly.
These adjustments can be factory but majority of the time, only toe is adjustable. Luckily there are aftermarket solutions to aid camber and castor depending on make and model.
Some of these include:
Adjustable alignment arms: These arms replace the factory suspension arms and have an adjusting knuckle on them. These are very common in track cars for the ease for adjustment on the fly.
Offset bushes: These bushes replace the factory bushes in the standard arms, there normally made out of polyurethane and have been designed to change the measurements due to their altered mounting points.
Camber pins: camber pins or also known as camber bolts, are a replacement bolt for some cars. These are designed with a lobe in the bolt so as the bolt is twisted, it changes the position of the component.
Measurement values change with each vehicle but most alignments are done based on the specs shown on the screen that are taken live from the machine.
Overall, this is a quick guide on the importance of getting a wheel alignment on your vehicle. If you're unsure about what you need or why you need a wheel alignment don't hesitate to give us a call to speak with one of our wheel and tyre specialists who are happy to give you a helping hand.