Bad Gas?

i would pull the plugs and take a look at them , to rich could mean a power valve failure, any backfire through the carb can ruin a power valve , it only takes once, unless you have a newer holley with the power valve protection . is it possible that you got some of that 10 per cent ethanol gas that they have here in the NE ? if so it may be to lean..my cars all hate that fuel..... even the 1500 ram hemi, that is suppose to run on that stuff..