Slick sizes for stock

[Lenny5160_v2]

I'm reading this and I'm thinking that maybe the tire I run on my S/ST car could be a solution. It is a Hoosier Drag Bracket Radial, 28 x 9. Before I ran this tire, I ran the 30 x 9 radials for 20+ years. I didn't notice any ET change when changing to the shorter tire, although that will depend on each combination relative to how it is geared.

Now, this tire is advertised as having a 9.5" tread width which probably makes it a no-no. I went out in the garage to measure my spare set of wheels with a traditional Stocker 30 x 9 radial on them, and the tread width is 9.375".

The rulebook doesn't exactly clear this up by implying that a tire up to 10" wide may be acceptable if the extra width is due to wear:

Street-type or drag slick tires, maximum 9-inch tread width.
Tires may not be altered from tire manufacturer?s original design
or pattern. Size of tire (new) must not exceed 9-inch wide x 30-
inch diameter (94-inch circumference). Tires may not exceed
10 inches wide regardless of wear.