Tire Pressure Variation
Posted: Mon Dec 09, 2013 8:39 am
Kinda slow here lately so thought I'd bring up a topic I'm a bit curious about to see what others think.
Just how accurate is setting tire pressure multiple tires during a race event? Let's look at this scenario, you get to the track let's say it's 75 degrees before your 1st pass of the day. Tires are "cold", rims cold, etc. You set your tire pressure at what you think works best on your car, keep the tire covered when it's in the sun, etc. etc. normal procedure.
You do the burnout, of course tire temps increase big time, along with air pressure. You make the run, get back to the pits turn the car around and head back to the lanes. Air temp is now 80+. Most likely you'll bleed some pressure off as the psi will go up with temp. Tires and rims are much warmer than the beginning of the day, rims are warm (brake heat), etc. You set the pressure back to the same setting. Do your burnout etc. and repeat each round with air temperatures and tire/wheel temperatures varying greatly depending on how much down time there is between runs.
Just how close do you really think the tire pressure is at staging with the different temperatures the tire / rim is at over the course of the race day?
Assuming the tire doesn't leak air, wouldn't it be more accurate to set the tire psi at the beginning of the day and call it good?
Any of you ever measure tire psi AFTER the burnout?
Just how accurate is setting tire pressure multiple tires during a race event? Let's look at this scenario, you get to the track let's say it's 75 degrees before your 1st pass of the day. Tires are "cold", rims cold, etc. You set your tire pressure at what you think works best on your car, keep the tire covered when it's in the sun, etc. etc. normal procedure.
You do the burnout, of course tire temps increase big time, along with air pressure. You make the run, get back to the pits turn the car around and head back to the lanes. Air temp is now 80+. Most likely you'll bleed some pressure off as the psi will go up with temp. Tires and rims are much warmer than the beginning of the day, rims are warm (brake heat), etc. You set the pressure back to the same setting. Do your burnout etc. and repeat each round with air temperatures and tire/wheel temperatures varying greatly depending on how much down time there is between runs.
Just how close do you really think the tire pressure is at staging with the different temperatures the tire / rim is at over the course of the race day?
Assuming the tire doesn't leak air, wouldn't it be more accurate to set the tire psi at the beginning of the day and call it good?
Any of you ever measure tire psi AFTER the burnout?