Amtrak has received federal approval for its trains in western Michigan and northern Indiana to increase maximum speeds to 110 mph.  It was announced Tuesday that the approval Amtrak and the Michigan Department of Transportation received comes after the installation and testing of a train control safety system on Amtrak-owned track that runs between Kalamazoo, Michigan and Porter, Indiana.  Authorities say the change with cut time from the trips, taking about ten minutes off the trips including the service  between Port Huron and Chicago.  More details are expected to be announced next week.