On occasion, atleast a few times a day, my car will stumble. It seems to only happen past 2,000 rpms, even when driving normally. Plugs are new, distributor's new (not remanned), wires are new, ignition coil's only a couple of months old.

Also, when I get on it and run it through 1st-2nd, it seems to be 'popping'... Like my exhaust is making little backfires sometimes.

Could this be a timing issue maybe?