Cause of Excessive Smoke after Adding Gas to Tank?

How much were you driving it before?

Couple of ideas, I'm sure others will post more. You could have gotten bad gas, which is causing the car to run like crap. Just because it's ethanol free doesn't mean it's always good.

If you hadn't been driving the car a ton before, it's also possible that when you added all the new fuel that you stirred up a bunch of crap in the bottom of your gas tank, and fed that crap into your carburetor which is now causing issues.