Addendum to letter 33913, GT3 DOT tires.
#34627 from Grand Touring Committee · Rule change · TB 23-08 (2023-05 Fastrack)
In GCR section 9.1.2.F.7.c.10.b, add the following:
"Any racing tire including DOT is allowed in GT3. Cars using 15” American Racer 23.5-10.0-15, bias ply, non-belted tire may do so
without the weight penalty."