One way to make your stunt scenes more realistic is to cast a stuntwoman as one of your leads, and that's exactly what Quentin Tarantino did for Death Proof. After she worked as a stuntwoman on Kill Bill, Quentin cast Zoë Bell in her first major speaking role. It certainly paid off with the incredible chase scene where Zoë's character is riding on the hood.
The lack of CGI, and the fact that it's not a stunt "double" meant the shots that they were getting of the whole scene, not just close-ups of the actor's face, really made for a tense watch. Talking about the drive, here's what Zoë said:
"There's no double, there's no CGI, it's all practical, and you're seeing that the person crying is the same one falling off the car. I think, on some deep, subconscious level, it triggers as 'real' to the people watching."