If you ran long endurance races where tires are falling off on most cars but yet a couple aren’t would you be paying more attention to internal or external? I’ve noticed a lot switching to a wintergreen mix internal. I used a lot of goat in the past but it seems to burn off fairly quickly. Even though it does give a ton of bite at first. I always was told wintergreen is similar but seems like wintergreen will last a whole lot longer in a tire before it falls off? These are big cars by the way. This site just has the most knowledge!