Not sure about aftermarket coils. I do remember a thread about adapting a set of Dynacoils to a late model SS. Maybe do a search. As far as performance gains, I think there may be some small gain in hotter coils if you have a modified engine. The gain wouldn't be in HP as much as it would be better throttle response. Your coils are probably more than good enough. I do have one of those New Volt ignition amps on my bike. I was able to open the plug gap to 1.5MM. The spark looks like it's from a freaking arc welder! I did feel a little difference in crispness after the install, but many argue a set of hotter coils will do the same thing for a lot less $. More than likely, that is very true. Anyway.... Those wires look pretty cool... If you need to unload them, IM me!