So you have the intercooler on now? I wouldnt worry about it with an intercooler and 8-10psi.
Does the superchip programmer advance timing? Like an engine tuning program along with firmer shifts? Make sure about that even with the i/c. Its not worth the better shifts if its also advancing timing.
The one time I've heard pinging (not so good gas) it sounded like valves "clacking" on an older car while going up hill or under load.. I turned the knob to take a little more timing out and it went away. and like ZQ8 explained it was in 90+ degree summer weather going up hill..
Small grey or black spots will be noticed on the core nose of the spark plug. In cases of severe detonation, insulators may be cracked and/or chipped. . It may be just a couple.. or alot of spots/speckles.
I was searching for an image of a spark plug showing detation and I found this:
http://www.prepsparkplugs.com
Supposed to vent compression when detantion occurs. lol. :bugeye:
Every image I find of a spark plug that has seen preignition shows it after the plug has practically exploded.
More on detonation:
http://homepage.ntlworld.com/celicagt4/what/detonation/det.htm