"I don't think you'll understand the true repercussions of what the 500 does for you until years down the road"

In this quote, Buddy Rice is referencing the impact that the "500" has on a person. It is most likely that he is referring to the Indianapolis 500, a popular cars and truck race. Rice is suggesting that the sense of accomplishment and achievement that comes with participating in this occasion may not be totally recognized till much later on in life. It is possible that the adrenaline rush of the race might trigger one to neglect the profound impact of the experience until they have had time to assess it. This statement highlights the concept that a few of life's most considerable moments might not be totally appreciated up until in the future.