Iowa’s top republican legislator wants to put the pedal to the metal and raise the speed limit on Iowa Interstates. House Speaker Brent Siegrist of Council Bluffs wants to boost the legal driving limit to 70 miles an hour on the Interstates.Siegrist says Interstate travelers making their way across the country are dismayed when they enter Iowa and find the posted limit at 65.Siegrist says most vehicles are traveling at 70 on the Interstates, anyway.Efforts to raise the speed limit have failed in the legislature recently, running into a roadblock in the Senate.