my car looks like a ricer so why not have flames? ha u guys are funny, but you dont see the point, these are to burn ricers!!! not be like one.! lol Anyhow, it cost me like a total of maby....40 dollars, the relay and the coil, its not expensive at all. Oh, and i dont have cats, i guess it wont do it if u do. too bad the vid dient capture the sound, it sound badass and is quite loud, ill try to get a good clip w/ the burn sound.