A few weeks ago I drove my aunt’s shiny red Mustang and, just because I’ve seen cool dudes do it repeatedly in movies and TV, I revved the engine. Several times. Just because it seemed like the thing to do. That engine made a lot of noise anyway, grumbling—some might say purring—through the streets of Chicago. It felt natural to really make it sing. I learned that the best use of the engine rev is when you’re driving slowly alongside or behind someone you know, so as to alert them to your presence in your banging car. Another use is when you’re waiting for your friend to get in the passenger seat; revving gets them amped for the open road on which a car with a big engine can cruise. [Caitlin PenzeyMoog]