We’ve been out at Circuit of the Americas for the past couple days enjoying the insane variety of good race cars that compete in Pirelli World Challenge, and we got an up-close look at how these guys set up and practice for a weekend of going fast.

Here’s a sampling of the cool cars racing in Texas this weekend and an up-close look at what goes on in the paddock, thanks to our photographer Kurt Bradley. They’ve been practicing up until today, Saturday, when the first qualifying sessions and races start up.

All photos credit Kurt Bradley