I’ve begun to notice that the tire load ratings being calculated in-game are not really in line with tires in the real world, with Automation ending up quite a bit on the low side of things. I’ve knocked together a small spreadsheet to show some of the differences I’ve found:
Note that the calculated load rating does not change with the speed rating of the tire, nor the type of tire compound, or the quality slider either, for that matter - it is, as far as I can tell, solely a function of tire diameter and aspect ratio. And as you can see, low-profile tires, which are becoming far more common these days, seem to have a fairly significant discrepancy compared to higher-profile tires.
For example, the 235/75R15 tire, which was a fairly common light truck tire back in the 80s and 90s, has a rated load of 1984-2094 kilos per tire per the Automation calculation, vs 2039-2271 kilos per tire from real-world examples, which is about 90 percent of what the real-world tires can handle. The 295/35R19 tire, which is standard rear fitment on a Porsche 991, has a rated load of 1235-1433 kilos per tire in Automation, versus 1764-1984 kilos per tire in reality, effectively two-thirds of what a real-world tire can handle.
The effect of this is that it begins to punish cars that use lower-profile tires as part of their design, which doesn’t accurately reflect the direction that real-world manufacturers are going, for better or for worse.
Any thoughts on this issue would be appreciated!