kart racer
do you think that this is why most people in N. america is in love with stockcars?
I don't know if most people are into 'stock' cars because of the sounds/smells of the sport, they certainly don't hurt the experience. I'm guessing your girlfriend is into like USAR Hooters Pro Cup or one of those other minor series, but I'd also wager that she isn't a stranger to the major divisions of stock cars (Nextel, Busch series)
I'd say that at first hand any NASCAR fan will tell you they like the sport because of the close racing and how they can relate to the drivers, yadda yadda...
When you look at the formula they made years ago it's really quite simple: 43 cars in a space ranging from 0.5 to 2.5 miles at an average speed of about 160 mph (a guesstimate) all viewable from one spot. And the drivers, apparently, all irradiate some sort of charisma that fans either love or hate, so they go to/watch the races to either 'boo' or cheer.
Then comes all the 'heritage' talk. Allison, Petty and Earnhart (to name a few) are basically household names in NASCAR-loving homes across America.
Some people like it, others prefer more complex or sophisticated kinds of motorsports.
But with all that said, stick with her,
kart racer.

Even if she's more into stock cars it's tough enough to find a girl who likes racing altogether.