MP/DC used to offer porting templates for the LA and Magnum style small block heads. Good luck finding any these days. I used to sell these for around $25 a set. I've tried to reacquire some and the only guy I've found willing to sell them is some dude in England who wants $150 a set.
Briefly looking through this article, it appears they are doing a deep bowl cut to clean up the throat of the port along with a 5 angle valve job and some minor hand blending. Its surprising to see such simple work yield such signficant results, but, I believe Steve Dulcich wrote an article on this exact same process about 10-12 years ago.