easiest and safest way to spit flames and pop?with NO damage to the engine?
if you have a decat,and prefferably an exhaust system (e.g. blitz nur spec) there is normally a small hole for fitment of a baffle in the back box exit,get a 10mm or 8mm bolt and sharpen the end of it on a grinder till its nice and sharp,bolt it through the baffle mount hole so that the point faces upwards,what happens is the tip of the bolt will get hot whilst driving,the tip of the nail is used as an ignition source due to the nail being hotter than the surrounding area.give it a few revs and any unburnt fuel will ignite off this causing a nice flame and popping sound to go with it
i know it seems hard to believe but it really works.
a little diagram i drew up quickly,excuse the crayons!