Camber, Caster, and Toe

Camber caster plates are popular modifications for many vehicles, including Mustangs. Though used on their own, camber and caster plates are also an important finishing step when lowering a vehicle or otherwise modifying the suspension of a vehicle.

Caster camber plates change the angles of a vehicle’s wheels, which many use to give a vehicle a wider looking stance. Whether you’re interested in getting a widebody Mustang or are trying to account for every variable when selecting your next set of wheels, camber and caster are two important factors to consider.

Camber Angle

The camber angle refers to the tilt of a vehicle’s wheels. Camber affects the way a vehicle looks when viewed from behind, and even a very small variation can impact the wear patterns of your tires.

Positive camber is what occurs when the top of the wheel tilts further out away from the body of the car while the bottom tilts inwards. Negative camber occurs when the top of the wheel tilts in and the bottom tips outwards.

You can check your camber while parked on a perfectly flat road. Most cars have an almost imperceivable amount of negative camber, which means for the most part the tires will look nearly straight up and down.

Lowering a vehicle almost always creates negative camber, causing the tops of tires to lean in towards the center of the vehicle. This causes uneven wear and can dramatically reduce tire life. This is part of why it’s so important to check camber and caster after lowering a Mustang.

Negative camber is seen as being desirable for performance driving since it allows a larger patch of your tire to remain in contact with the road, even while cornering. Positive camber on the other hand has very few practical applications and is rarely seen on roads.

Though negative camber is great for driving around twisty corners, for drag racing most drivers prefer a neutral camber. Keeping the wheels and tires straight up and down keeps the maximum amount of rubber directly underneath the car, which is ideal for straight-line speed.

For cars with MacPherson strut suspensions, there is usually enough camber for average use vehicles to turn corners with only a little traction loss. For vehicles that are driven more aggressively though, there usually isn’t enough adjustable camber to compensate for how the tires will want to adjust while cornering.

The solution here is to add “static” negative camber, effectively changing the starting point but not the range.

Caster Angle

Caster refers to how far forward or backwards the wheels of a car are in relation to their steering pivot angle. Just like camber, caster is measured as being either positive, neutral, or negative.

Positive caster means that the wheels will be at an angle towards the front of the car, while negative caster means that the wheels will be at an angle towards the rear of the car. Some movement in this angle is going to occur with any vehicle, and is a necessary part of a vehicle’s suspension.

While parked on a flat surface straight from the factory, most vehicles will have a slightly positive caster, and positive caster is an important way that handling feel is transmitted to the driver.

The only experience you are likely to have with negative caster is with the wheels on a shopping cart, and if you’ve ever experienced those you understand why they don’t make an appearance on modern vehicles.

Toe

The other angle to understand with regard to wheel alignment is what’s known as “toe-in vs toe-out” which is basically exactly what it sounds like. When a car toes in, it looks as though the forward edge of the wheels is going towards the center of the car. When a car toes out, the opposite is true.

A neutral toe position is going to be optimal from a position concerned with tire wear and speed. But, the natural drag of the tire can actually create a slight toe-out. Thus, you’ll find a lot of enthusiasts aim for a very slight toe-in while they’re aligning their vehicle, but only to counteract the toe-out and create a true zero.

Camber Caster Plates

Camber caster plates are designed to add static, or permanent, positive or negative camber to a vehicle in order to expand the range of camber that it’s capable of reaching. Your stock caster camber plate comes as a single unit, while aftermarket sets come as two plates that allow you to create the exact setting that you want.

Many aftermarket camber caster plate sets will also mount higher on the strut, increasing strut travel.

Camber bolts are another way to adjust camber, but they typically don’t have as wide a range of adjustment as camber plates do. Camber bolts are typically used to correct camber back to factory-correct after lowering a vehicle, but they don’t have a wide range of adjustment beyond that.

Essentially, if all you’re trying to do is return to factory-settings after lowering your vehicle, then camber bolts are a great way to do that inexpensively. If you want a greater range of adjustability though, then you should go for the plates.

Camber Caster Adjustments

Though visually assessing your caster and camber angles is good for knowing when you need a tune-up, if you’re planning on adjusting your camber or caster angles it’s important to have a tool that can measure both accurately. Having wheels with uneven caster-camber numbers can seriously affect your handling as well as your tire wear.

To set your caster/camber, you’ll need to find a level surface and make sure your wheels are pointed straight ahead. Then you can use a caster/camber gauge. While professional alignments typically use turn plates, a simple bubble gauge is sufficient.

Which Adjustment Is Right For You?

It’s good to be able to read your camber and caster angles since they’re an important aspect of proper wheel alignment. What you ultimately set your camber, caster, and toe values to depends a lot on your individual vehicle, and your handling preference.

Typically your stock settings will look like 1/8 inch toe-in, -.6 camber, and +1.9 degree caster. This is a great starting point, and then you can make minor adjustments from there to achieve your perfect balance of tire wear, ride feel, and handling sensitivity.