1995 Chevy Camaro Smoke from my exhaust?

I can never tell in the day time, but when I drive at night I can see what looks like smoke in the headlights of the cars behind me only when I take off in my car. I can see it in my rearview mirror and only when I kind of go hard on the pedal. I only use supreme gasoline in my car because Chevy reccomends it for the Camaro Z28. Am I burning oil when I floor it like that or could it be something else? I'm a little worried. Also, I read a question about a rattle in someone's engine and I had a mechanic say it's called a spark rattle. He suggested I use supreme gasoline (this was before I knew the manufacturer suggested it). I have been using supreme for six months now and it still has this rattle. I also use cleaners such as seafoam to try and get rid of it. Am I going about it the wrong way? Is there anything for that?