man last weekend i was doing about 160 uphill on the 400 going to burls creek I look down at the speedo and go wow thats fast and I was the slow mover lol and yes my truck can do 160 without pushing it
yeah,that half inch makes a big difference. it throws your speedo way off,meaning you're doing more RPMs,which equals to your speedo showing you going faster than you really are because the tire is smaller.