Thanks for putting the info out there - interesting!
Here are Toyos recommendations for the tire:
Operating Temperature: 160°F to 220°F
Hot Inflation Pressures: High 30s to Low 40s (psi)
Camber: -2.5° to -5.0°
Caster: As much positive as possible
These recommendations are for a fairly broad range, and are identical to the RA-1, FWIW. There may be aspects to our specific application that are different
We run a wider tire the same width rim as SM, and SE30, for example.
Digging around Toy's website, I came up with a SM setup guide (see below). It is meant for the R-888, but has some useful generalizations for doing tire temp testing. The presssures and camber settings that they recommended there are very different than the RA-1, or RR.
Spec Miata Setup Guidelines
...................................
Air Pressure
The R888 can be used at lower hot pressures as compared to the RA1 because of its design.
Decreasing the air pressure will improve contact pressure and footprint shape. A recommended hot
pressure range is 32 – 38 psi. For a light weight vehicle such as the Spec Miata, 32 psi hot is a good
starting point.
Tread Temperatures
The optimum tread temperature for the R888 is 160°F to 220°F. Below 140°F and above 250°F the tire
may not provide sufficient grip. Generally there will be a 25°F temperature gradient from inside to outside
shoulder, with the inside shoulder being the hottest. Most distance and time on a race track is in a
straight line therefore, the inside shoulder is hottest because of negative camber. The same
temperatures across the tread face should not be expected.
Understand the track layout before pit entry. If for example there is a long right hand turn before entry, the
left tires will be hotter. Take tire temperatures and pressures after a few laps to get the temperatures and
pressures stabilized and come in after a hot lap.
Camber
To maximize the potential of the RA1 a lot of negative camber might have been required. The R888 on
the other hand produces more camber thrust at the same camber angles as the RA1, therefore less
negative camber might be beneficial. Reducing negative camber will improve contact pressure
distribution across the tread face improving wear. Start at -2.5° in the front and -3.0° in the rear.
Analyzing the tire temperatures, wear, and chassis behavior will help you dial-in the optimum camber for
your setup.