Tire tech is something that every driver can experiment with to improve their car’s handling, lap times, and better manage tire wear. Below are some very basic rules for getting your tires in to their optimal temperature and pressure for maximized grip.
The first thing to know is that tires have optimal temperature ranges at which they were engineered to perform. The pressure in your tires before you drive is called cold pressure. I’m sure you can guess what hot pressure means. The tires will heat up as your are driving and the pressure inside the tire will increase. If you are using a standard street tire, check your car’s psi rating. A good starting point for psi is around 2-4 units under the car’s rating, with a target hot pressure of 2-4 psi above that rating
If you are using performance tires, there should be recommended specifications for hot pressure from the tire manufacturer. For example, the Toyo R888’s specs are 28 – 40 psi hot. Let’s say you’re in a heavier car weighing around 3300 lbs. You may want to aim for a mid-high psi, such as 32-34 psi. You would start at around 28-30 psi so that the tires can heat up, increase pressure, and you can bleed them all down to spec after about 5 laps. This will set your tires up to perform at the ideal psi while on track.
Tire temperature across the tire is also a good indicator of whether or not you need more pressure, less pressure, suspension adjustments, or driver adjustments. As general rules:
If the tire is hotter in the center it may indicate the tire is over inflated.
If the tire is hotter on the edges it may indicate the tire is under inflated.
If the tire is progressively hotter towards the outside, the car may need more negative camber or is being over driven.
If the tire is progressively hotter towards the inside, the car may have too much negative camber.
These are just the basics. A lot of this will be the driver experimenting with what they like and dislike. However, it doesn’t cost you money to let air out of your tires. Might as well try your hand with this at your next track day.