We already refine more than we use and export the surplus.
That said, there have been several refinery expansions to take in more of the light sweet oil.
But it doesn't make sense to to spend money to use a more expensive feedstock. If years from now, we are exporting a million a day of $100 oil, it will because we are offsetting it using $85 oil brought in, keeping prices lower in the US.
Wow so we export refined products? That is really sh!tty.