Originally Posted by 2door
Old timers, hot rodders, used to install a spark plug in the tail pipe of the car. They would shut off the ignition, floor the gas pedal to get a rich mix coming through the exhaust then turn the ignition back on. The spark plug would ignite the fuel mix in the tail pipe and you'd get a bang/flame. The rat rod guys are now using propane and an ignition source such as an igniter or a spark plug. Not a good idea on a 2 stroke. You might get more bang for the buck that you want. Don't try it. I'm serious; you could really hurt yourself or anyone standing nearby.
This is true & it is definitely dangerous no matter how it's done... and I'm not recommending it w/these lil china engines (poor/shoddy construction & tailpipe WAY too close to fuel & rider), but jus' as a BTW - the slight refinement used in some show vehicles built for this is a manually activated choke (fuel source & regulation) and a switched, secondary ignition system with the spark plug installed near the end of the exhaust (as mentioned) - the manual choke allows somewhat more controlled mixes, bursts and duration of burn. The propane variant is just terrifying TBH (flame amount & backblow potential).
Thing is even aside from the obvious hazards, I always thought it looked... odd. Sure, fire is cool lookin' but srsly, if a vehicle is doing that it can only mean one of two things, it's equipped as a show queen for bling's sake alone or something is seriously wrong with that engine heh Nothin' wrong w/show builds ofc & to each their own, but as I prefer equipment/mods to do somethin' a bit more than just lookin' cool - my first reaction is always "wha? o_O busticated lol"