Put simply, the amount of suspension travel and how much camber is gained as the suspension travels will dictate how much static camber you need to run. As a rough guide, here's a list of camber settings for various suspension layouts and vehicles. This is meant to be a good starting point for a street car setup, but will require adjustment to fit your needs and vehicle specifics. These settings are meant to be a good starting place for a street car with street radials.
Your vehicle may prefer more or less camber. Race teams will know how much camber to dial into their car from thermal tire data tire tread temps , tire wear patterns, previous track experience, and driver feedback.
Well-funded teams will have additional data from load cells, shock travel, acceleration sensors, images, and onboard telemetry using thermal cameras. At proper camber settings the tire will exhibit stable and symmetrical temperatures across the tire surface during cornering.
Excessive heating on the inner or outer third of the tire can be indicative of improper camber angle, although not conclusively. Road conditions can also demand more or less camber. Loose gravel and wet pavement both limit the amount of overall tire grip available, which necessitates less static camber. Drifting requires a rather unique setup since it pairs the need for good tire life and performance.
Modified steering geometries spindles, tie rods, etc. It's important that the static setup compliments this and any other bump geometry. The rear should have near zero camber to provide strong forward grip and more importantly, to last quite a bit longer. By using the entire tread face you will evenly distribute pressure along the tire and heat it more uniformly. Positive camber is when the top of the tire extends outward, and the base of the tire tucks inwards. This is rarely ever seen on a road car since it will reduce road handling capability.
Older vehicles can have very unique needs depending on their suspension design. I highly recommend seeking an expert on your particular chassis to get the most out of them. Bias ply tires react very differently to camber angle due to the differences in their construction compared to radials. Using the above recommendations, which are meant for radials, can result in lackluster results. Typically, you will run a bias ply tire with considerably less camber. Again, I recommend consulting an expert for further assistance on your vintage setup.
Cornering with zero camber causes one side of the tire to unload, while the other side of the tire takes more load. This is unequal load distribution and lowers the overall available grip on the tire, just when you need it most: while cornering! With negative camber, the force distribution along the contact patch is somewhat unequal while driving in a straight line. However, when cornering forces and carcass deflection come into play, they can negate the effect of negative camber, equalising load distribution along the contact patch.
This maximises the available grip on the outside tires which are the ones taking the heavier load , exactly the moment when the car is limited by its available grip.
Tradeoffs of using camber As always, nothing comes for free. While camber can help cornering, it causes additional heat, more tire degradation and uneven wear pattern on the tires. You should also realise that you are trading off traction on a straight line braking and acceleration with cornering grip. This means that the track profile is a determining factor on how much camber you want to run.
Camber and vertical stiffness Vertical stiffness of the tire is hugely tied with tire pressures, as discussed in 5. This is mostly to be considered on tires with high sidewalls. Having the tire inclined at an angle may cause the sidewall to deform a little. While cornering, positive caster causes the following effect. If there is more positive caster, the dynamic wheel pressure will remain on the inner wheel, thus increasing grip at the front of the car.
Normally speaking, setting caster is very difficult, if not impossible. Tyre wear. Straight line stability. Moment of cornering. For minimum tyre wear, it would be ideal if tyres were parallel while driving. In other words, no positive or negative toe, so 0 degrees. With a front-wheel drive car, this can be achieved by having a little negative toe-in static conditions. A rear-wheel drive car should actually have slightly positive toe-in such conditions. This is particularly applied for street use.
For racing, it depends on the type of car, tyre and wheel geometry. For a rear-wheel drive car, negative toe at the front wheels and positive toe at the rear wheels is quite usual.
We see this mostly with front-wheel drive cars, but it is also found with rear-wheel drive cars with independent wheel suspension. When releasing the driving forces, the momentum of the drive shafts causes the suspension, as well as its joints and connecting components, to be subjected to a high load. This will lead to distortion of the suspension's construction.
The driving wheels want to go forward and will get positive toe. This especially applies to street cars. By applying flexible rubbers for the purpose of comfort and noise reduction, there is a lot more movement in these types of suspension. Which is why static tracking often starts with some negative toe. High toe-out values will lead to the inner edges of the tyres being 'eaten', which will lead to additional wear and tear. A lot of toe-in will especially subject the outermost part of the tyres to a high load.
Negative toe will mainly improve the steering response. Positive toe will mainly increase the straight line stability. Sometimes toe-in or toe-out is applied for a different effect: tyre temperatures.
It is very important for racing tyres to reach a proper operating temperature, in order to ensure maximum grip and performance. When tyres remain too cold, the so-called scrub effect of tracking may provide a solution. This scrub effect also has a cleansing effect on the tyre tread. This means the brakes can be applied more forcefully and there will be more grip available in the corners.
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