Measuring tire temps at AX, What am I doing wrong? Options

[Joseph Mills]

At the last AX, after several runs, I went from 36# to 30# for the front tires (Hoosiers). At 32# and above, the inside was about 5 deg. hotter than the outside. Below 30# the outside started heating. At 30# they were about 117 deg. all the way across the tire. Good. And the car does not push.

The rear tires were about the same temps. However, even when I went as low as 26#, they are STILL about 6+ deg. hotter on the inside. And at 26# the car was starting to get a little loose, but easily controllable. Below are some things I've considered, but really, I don't know where to go from here.

My car does have 1/2 deg more neg camber in the back than the front....

It was a short AX - around 38 sec's with some straight ahead driving - which would tend to heat the inside tread....?

Maybe I need a faster/longer AX? Or can you only do proper readings on a skid pad or figure 8 only....?

Could the engine heat up the inside of the tires? Usually spend 5 -10 minutes with engine idling and slowly creeping up the line.....???

My "pyrometer" is very cheap, but seems to be very reliable with repeated readings.

Any ideas out there??? HELP! (IMG:style_emoticons/default/ph34r.gif)

[Joseph Mills]

Since Brad says so, I'll try 40 degrees on my Hoosiers....what can it hurt?
Whut a great thread. I'm finally begining to understand the black art of tiar temps/pressures. (IMG:style_emoticons/default/wacko.gif)

JP - You'l need ice packs (hangover thangs) to cool your tars down ta 40 degrees.

EPK - I have a friend that runs the same tire @45F/50R

The question that begs to be answered is who is faster? The guy with skinny tires @ 40lbs which get hot & sticky, or the guy that's over tired & under inflated, but with a big-ass footprint?

I'm gonna spot check different cars this weekend for tire temps. I wonder if even the skinny tires get hot. It will be a small course this weekend due to some outside restrictions, BUT there will be two continuous laps for each timed run. Should be fun.

Becoming more determined each day to find a skipad. (IMG:style_emoticons/default/mad.gif)