Well if you got the flames through a flamethrower or something, that'd just be cheap and stupid.

On the other hand, flames resulting from the actual car would be so awesome! I doubt that would ever happen though.

For example, I saw this video of a car on a dyno and the catalytic converter was simply glowing red hot. Some headers will do that too, after a night of hard driving.

In my mind, that's almost admirable!