We do have several car museums in the US, but the problem is always getting people in the door. The Barber Motorsports Museum in Birmingham Alabama has a great advertisement at the airport, its a Lotus 109 behind glass at baggage claim! I went last week for work and walked right on past it, and while getting my bag saw the rear wing and took a look at it afterwards. It was a pretty neat way to advertise while also being pretty cheap.
The other problem with the US is the size of the country. I'm going to Japan in July and had wanted to go to some of the car museums near Twin Ring Motegi and Suzuka, but with everything else we have planned it doesn't work for our trip. The US is huge compared to it, so even if it was in Indianapolis, it'd be dead most of the year, and NY/LA don't have much of a motorsports presence per say.
