If you are running stock class, and your competitors are on Azenis, if you can afford it, get the R-compounds. Usually, the estimate is that they will be about 1-2 seconds faster. If you can't afford the R-compounds, Azenis would be a great non-R. Thats what I run. Cheap, yet sticky.The tire must not appear on the following list, which may be altered at any time by the SEB upon notification of membership: No tire models are currently listed.
The model of tire must be listed in a current or previous two years of the Tire Guide and Tread Design Guide, or otherwise be approved by the SEB. The tire model must have Department of Transportation approval.
Within each tire model, the sizes which are available must be equally available to all competitors. Tire model variations differing from standard specification, delivered only on a limited basis, or only to selected competitors, may not be used.
No racing tire or recap (on any casing) may be used.
Each tire model must be sold in at least four diameters, with a total of at least six sizes.
Tire must fit the allowable wheels and fender wells without modification.
Each tire must have non-zero measurable tread depth (i.e., points where it is possible to obtain positive measurement values) as described in Section 3.3.D. Tires may not have cord visible at any time during competition.