NHRA sanctioned tracks
are allowed up to a +/- 1% grade or slope to the track. IHRA uses a +/- 1/10"(?) specification. I'm not sure, but suspect that is a 1 inch in 10 foot grade change (.8%), maybe?
Anyway, that 1% looks like a lot from a distance or on TV from a wide shot. And like at this track, the track will often go "uphill" at 1% after the finish line.