I have a 03 dakota 4.7 V-8. I finally got the 91 setting on the superchip programmer to work without pinging exxon gas was casuing my pinging. now I noticed that the temp guage is just below halfway now. before it was like a quarter inbetween cold and the middle. is this casused by the 93 octane burning hotter and longer in the combustion chambers? or is my thermostat going? it started this when I went to the 91 setting.