The only surge I noticed was just before home, so at the hottest temps. I can pull plugs later and get pics. They are E3 plugs and I have never used them before. The combustion side of the plugs are black with deposits, the electrode side is gray in color on the 2 I pulled. I didn't change the tune after changing the gears from 3.91. It is noticeably different as cruise RPM is different and starting from a stop has a stumble whereas it didn't before, but I assumed that would happen.
