I am running 80s on all 4 corners with Promaxx jettable plates and 64 in the center carb. On my AEM gauge, it reads mid 13s-14s at idle. On cruise in third gear it's mid 12s and on the freeway its mid 12s also. Number 7 plug is dark and fouling so I changed the drivers side rear jet to 78. At idle the gauge reads 16s now. At cruise and freeway it reads mid 13s-14s now. Should I put the jet back to 80 and fool around with the mixture screws or leave 78 in and fool around with the mixture screws? I don't like seeing it read 16s. The outboard screws are a tad bit more than 1/4 out. This is a new plug with some idle time.