This stretch of road is frequently monitored by Arkansas State Police, Boone County Sheriff Dept, and Harrison City PD. The Harrison speed limit is 45, then 55 on the outbound side. Due to the new interchange with wide lanes, drivers often think they are entering freeway speeds, but this is not the case. The welcome center is a great place for traffic monitoring. Ignore the locals that will tailgate you if you are proceeding at the speed limit, or outright passing you up. Stick with the limits.