Yep Sling is right. They should have figured this one out last winter.
They do have ways to slow the cars down on the ovals, but the problem is that the engineers keeping making the car faster. Even with all the reductions in power and lift/drag ratio, the cars are faster than anything in the history of racing.
Which is why you do a thorough test at a new track to make sure the cars aren't too fast. Duh!
PS I did a rough calculation and I came up with 3 g AVERAGE including straightaways at this track. I am guessing they were up near 6 g in the turns. I'm sure F-1 drivers could handle it, but flabby guys like Tracy or Andretti were probably gasping.