This is not uncommon. Many performance cars over the years have had tires custom spec'd for them. An example that comes to mind is the Bridgestone RE070, whic

This is not uncommon. Many performance cars over the years have had tires custom spec'd for them. An example that comes to mind is the Bridgestone RE070, which for a while only came in exactly one size, because it was for the mid-2000s STI. It did come in another size a bit later when the GT-R started using it as the factory tire. I want to say that the sixth generation Camaro SS 1LE also had a custom tire, though I think it comes in more sizes now.