After a very good weekend at TWS and the first where I had a tire pyrometer available to me I think I have generated more questions than answers.

I did spend the morning getting the pressures right.. with the fairly low ambient temperatures (upper 30

 

Tire temps need to be after hot laps without cooldown. Tire pressures are much more stable. The tire looses heat to the track and if the outside of the tire touches the track at the limit, but the inside touches the track on cooldown laps, your cooldown lap will lead you to wrong conclusions.

 

Chris,

From what I read and contrary to popular belief, the best tyre performance is achieved when the inside of the tyre is 10-20F hotter than the outside. This, however, is not of much use to common mortals: the tyre temps across the surface vary amazingly quickly depending on whether you are accelerating, braking, turning left or right. Static temps are good to detect conditions that are way out of line but not for fine tuning.

Now, if you had a non-interference real time temp logging device...

 

Grassroots Motorsports has a nice article on this very issue this month. They recommend using alignment to generate less than a 10 degree variance across the tire.

 

Thanks for the input.. you have confirmed my suspicions. My pyrometer is good for interesting but not terribly useful information.

I had actually come to that conclusion after a few sessions when it was very obvious from the feel of the tires that they heated and cooled at various places on the track. A brief loss of focus or a pass forcing you off line can but stresses on the tires that put them out of the sweet temp range until the next cooling straight.

It may not be a great tuning aid but I