My grandfather used to talk about putting a spark plug in the exhaust of old hot rods to make the "flame-thrower" effect. I never really considered doing anything like that but the topic makes me curious. Would that hurt an engine? Isn't there a chance it would ignite everything in the pipe going right back into the engine? The idea sound like a cool novelty but also a little dangerous. I think it would look cool on my "off road use ony (wink wink) america" but not if it's at the expense of my ride. Any thoughts?
