I need some help with my car as it will black the plugs in 100 miles or less. I just put in a fresh set and took a 120 mile ride and came back and plugs were jet black. Car seems to run good with no issues. I have tried Autolight 103 and 104 plugs as well as NGK-7's. I do have Champion Alum heads and these are the plugs they recommended. I do drive this car almost everyday and I go race about once a month. Thanks for any help.