SOURCE:  INDYCAR PR 2016 Verizon IndyCar Series Rulebook Updates INDIANAPOLIS (Dec. 21, 2015) – Refinements to the 2016 Verizon IndyCar Series rulebook, distributed to teams and suppliers Dec. 19, clarify procedures established by INDYCAR in the past two seasons and highlight ongoing efforts to improve the overall fan experience in the upcoming season. Areas of…