Ah ok thanks I just saw a track in Pa post on Facebook they were taking the tops off, kinda like NASCAR's old convertible division where it was sometimes the same car without the roof.Honestly not much in terms of removing that small roof panel. It's a cosmetic gimmick that I've seen various late model and modified series use here and there for the last couple decades. While high end late models are now highly aerodynamically sensitive, at most levels I've seen this done, there isn't going to be much difference and it just allows fans to see the drivers more.