Colder Spark Plugs Stop Pinging?

Well it doesn't run on. I guess I understood if it runs on after shut off? It only pings some if I get on it say if I'm running about 30 to 35 miles an hour and then hit the loud pedal. Especially if I have been driving it a good while in hot summer weather. It tends to ping and then can't smoke the wise guy beside me. I also think the ethanol in the gas even though it's 93 octane, is part of the problem. I would go non ethanol but Want to make it work with the gas readily available to me at any pump.