On the weekend, I pulled the carb to give it a clean and put on a 1/2in phenolic spacer to keep the carb a little cooler. I was wondering if this could have caused pinging at all. I didnt touch the timing, but I did change the oil (25w50 Penzoil) and coolant. The engine seems to be running hotter than it used to, but before yesterday I had never heard it ping before. I've read that the pinging could be causing the increase in temp, is this right? Should I look at backing off the timing first?