You are nuts.

Think about all the grit, grime, and God knows what else swirling above and around a public roadway. And every bit of that gunk will find your model.

An 18-wheel cockroach barreling past you at 70mph could create enough turbulence (a "wall" of air pressure; go past one in the opposite direction with your window down) to wreck the model, or at least damage it. Worse, create damage that you don't notice on the pre-flight.

I could go on, but I think you see that I, for one, consider this a real bad idea...

Steve