mine came with a whole in it specifically made for a screw
check out toys 'r' us or target for a toy car called "Modifiers" but make sure you get a Series 2 1/43 scale.. not the Series 1 1/64 scale. the series 2 comes with replacement mufflers for the car. i just used one of them.. granted i bought this toy before i even knew about the mini r/c world, so i didn't buy it specifically for the muffler.