Is there any place to get 93 octane near Waterloo? I live in Wisconsin where the 93 is easily available, but I drive to Deere in Waterloo very frequently so I've used only the 4+ 91 octane tune. I'd like to see what the 4+x has to offer but its hard purging the 91 from the tank. I may have a trip to Ankeny in my future for a mid-flight refueling.
