DAYTONA BEACH, Fla. (AP) — NASCAR has tightened the restrictions for 2018 on Cup drivers who want to drive in lower-tier race series. Drivers with more than five years of full-time experience who race for points in the Cup series will be limited to a maximum of seven Xfinity Series races and five races in the Truck Series. The Cup drivers will be ineligible to compete in the regular-season finale and playoff races in each series, as well as the Dash 4 Cash races in the Xfinity Series. It's a change from the rules put in place for this season that limited Cup drivers with five years of full-time experience to 10 Xfinity races and seven Truck races. ___ More AP auto racing: http://racing.ap.orgRead more on NewsOK.com