318 running like crap

Thanks for all the help. I timed the car and its running alot better. Gonna change fuel filter again. Its a little sluggish at start but runs pretty good down the highway. Another question i have is after driving the idle is really high. My Dad seems to think the carb needs rebuilding. Its an older Holley carb. Also he thinks i should change over electronic ignition? Will the carb make it sluggish? Also when i changed plugs they did not have enough autolights 65 so i put NGK plugs in. I think i gapped them 35 or 40