This is a vid of me playing with retarding the ign timing a bit further and seeing the outcome. This is extremely retarded (like 15deg below 4000rpm) usually only 5-10deg will give a few pops. The engine is stock and has a supercharger strapped onto it so it sees plenty of load at 400hp. Mine will shoot a few flames on decel but that's a by product of slight ign retarding and allowing some fuel injection on decel to keep the cylinders cool which also helps with throttle response when back on throttle. In short.. do what you want with your engine, but my recommendation is; go to a specialist who knows what they are doing? and ask them to tune in the pops and bangs so that its still safe. I dont care too much about my engine so flames and pops dont really bother me. If it blows up.. its something i get to fix.