I know how its done Years ago it used to be done on carburated vehicals by loading up the exhuast with lots of unspent fuel and lighting it off with a few good revs with a spark plug in the tailpipe now days with fuel injected cars its done a bit different. you can buy kits for it online for 6o bucks and up. in the tailpipe you install a fuel injector and a spark plug the wires are connected to the same in cab switch, and it gets a little more complicated than that but thats the safest way to do it now days it's not that hard and makes for a good show. Im considering the possability myself