Instructor’s Insight: Tire Pressure
Instructor’s Insight:
Tire Pressure
First things first: bring a tire gauge and a piece of chalk to every event.
When you arrive at the event, mark three spots around the edges of your tires — basically the 12, 4, and 8 o’clock positions. Some tires will have multiple triangles like the ones shown in the picture; others will just have a line. If your tires have triangles, use them. If you have difficulty finding a good spot to mark, ask us! Take the valve stem caps off and put them in your glovebox.
When you grid for your run group, check your pressures. A decent starting point is to look at the sticker inside your driver’s door and increase the manufacturer’s suggested front PSI by 3. The suggested rear PSI should be okay.
After your first run, check your chalk marks and tire pressures. If your chalk mark extends above your triangle like in the first picture, reduce your air pressure by 1 PSI and run again. Continue doing this until the chalk mark ends at the tip of the triangle. When you find that number, write it down! This will be the PSI you want to set your tires to for each run.
-
Even though there might be slight differences between the left and right tires, keep the PSI the same.
-
Front and rear tires usually need different pressures to maximize the contact patch.
-
Tire pressures will significantly increase as they warm up, and it is common to have to bleed off multiple PSI to maintain the ideal pressure.
-
Too much pressure leads to less grip.
-
Too little pressure leads to the tire showing marks on the sidewall.
-
IF YOU OVERDRIVE YOUR CAR, YOUR TIRES WILL ALWAYS SHOW EXCESSIVE ROLLOVER! The problem is not your pressures, it’s your inputs. Adjust that first.
There is much more to this, but following this simple outline is a great start and will get you 90% of the way there.
