There's a long-standing catchphrase in the automotive world: "red ones go faster". I'm sure the fact that Ferrari, arguably the world's most famous sports car marque, has historically used that colour as their definitive hue has at least something to do with it.
It turns out that red cars also sound faster. Tests done by researchers at Technische Universit??t M??nchen have shown that, for a controlled engine sound, if it's accompanied by visuals of a red car then the listener perceives it as louder.
In most cases, red cars seemed louder than blue or light-green cars for the same sound. Dark green also seems to elicit somewhat higher loudness ratings than light green or blue.
You could try it on with the police the next time they pull you over and you drive a red or dark green car, but I'm not sure how convinced they will be in the latest psychoacoustic research coming out of Germany.