Firing problem??

[flyby84]

So,I get my car out for some warm weather cruising only to find out it runs like crap! It started out popping back through the carb and pinging in the exhaust. I tuned it up (cap,rotor button,plugs, wires) and now unless you run the timing advanced to where it won`t start once it`s warmed up it`ll miss like it`s got a bad plug wire or two. It seems like a weak spark to me but I replaced the coil,ignition module and the distributor module last summer. does this sound like maybe a bad coil? Any help would be great! Thanks.