I think it would be cool to have a tyre temp estimation display (a plugin or so) – as racing simulators like rFactor or Live for Speed – based on real car obd data.
It could use as inputs:
– ambient temperature
– run time
– avg speed
– lat/long acceleration
– driven wheels spin

It could estimate asphalt temp by adding some °C to ambient temp based on time of the day / year
i.e. ambient temp = 30°C, time August 15, 17h00, adds 20°C => est. asphalt temp = 50°C
i.e. ambient temp = 28°C, time August 16, 6h00, adds 2°C => est. asphalt temp = 30°C
i.e. ambient temp = 0°C, time January 5, 6h00, adds 0°C => est. asphalt temp = 0°C
Of course seasons depends on emisphere location, and heat transfer rate should be investigated.

As car parameters:
– front / rear tyre width
– front / rear weight
– front / rear track
– front / rear tyre pressure
– wheelbase
– tyre type (summer / winter / slick)

For each tyre type should be entered an optimal temp window (i.e. 60-80°C for summer tyres, maybe 5-15 for winter tyres), a below optimum range (30-60), an over optimum range (80-90) and the other two extremes (30- 90+)
Friction coefficient ? (mu) could also be considered as a parameter, so as correction coefficient.

Output would be four rectangles on the four corners representing tyres with color changing according to estimated temp (typically blue = tyre cold, green = tyre optimal temp, red = tyre too hot)

Anyone willing to crunch the data, get a super equation and build a plugin?

Thanks Ian, appreciate

If your car has real tire pressure sensors (and not just a pressure monitor based on ABS speed sensor readings), then you could baseline the temperature to ambient at the beginning of the first trip of a day with ‘cold’ (ambient temp) tires, and compute the temperature increase from the pressure increase using R x T = P x V. I.e. temperature (in Kelvin) is proportional to pressure times volume, so if at the beginning of the trip the temperature is T_0 and the pressure is P_0, then later T=T_0 x P/P_0 (volume being constant, and assuming you are not losing any significant amount of air during that trip).
Long term air loss would be calibrated out each time when you start your first trip of the day.