Originally Posted by Jhill

This is what I meant when I said most cars I have worked with (so that's not the z as I only have my own for comparison) but if they ping it is right at throttle tip in from cruise and is momentary. Typically this is in a part of the map with high ignition timing as they want good throttle response and max torque since you are trying to accelerate. Not every car does it even within the same type of car and climate and fuel quality play a roll (acura MDX were fairly picky since they are also heavy and use high comp ratio as well). As for long term damage, not being able to hear if yours is a light ping that instantly gets corrected or if it's bad knock and not correcting would make a big difference, the first one I personally have not seen one fail catastrophically by light ping that gets corrected quickly.

Again if you really want it gone I would go to Seb and he will actually tune it for 91 octane with two ign maps one for summer and one for winter (hot climate/cold climate).