If you've researched or perhaps even purchased the Vitour Tempesta P1 tire, by now you know that the SCCA Solo Event Board (SEB) has added them to the National Event Exclusion List: 

The Tennessee Region SCCA Board has decided to allow this tire only in classes not restricted to 200tw tires per the SCCA Rulebook (such as Modified or Prepared classes). If you have any questions about the legality of this tire in your class please email our Solo Chair for clarification.