After some cursory research it looks like the thing most correlated with a large bump in academic rankings is a large decrease in acceptance rate. There haven't been many big movers over the last 25 years but Stanford, USC, Texas, UChicago, and WUSTL stand out. I find this interesting as Stanford, USC, and Texas have all had extremely successful football programs within that time period and anecdotally, I received a ton of mail in high school from USC, UChicago, and WUSTL. It seems that marketing is important for application rates and football success is a large part of that. Jack Kroll be damned.