You'll cruze right through the middle of Indianapolis on the way. I live here and you need to stop at the Indianapolis Motor Speedway. See the museum and pay to go around the track (in a bus... sorry)
http://www.indianapolismotorspeedway.com/
Also check out the new John Force museum and new fab/machine shop - it will blow your mind. Here's the address.
http://www.johnforce.com/allford.html
Catch Lunch between the museums at Union Jacks. It's a chicago style pizza joint right by the track and it also has a huge display of motorsports stuff. The pizza is great !
http://www.unionjackspeedway.com/
There, I burned an entire day for you. My work here is done....
Jim