It depends heavily on how bright that specific track lighting is, but in general night motorsport is demanding. With an 80D, 1/500s+ usually means pushing ISO high, and your f/4 and especially f/4.5-5.6 lenses are not ideal for this. The 100-400mm is much more of a daylight lens here; the 70-200mm f/4 is the better of your two options, but still limited for night action.

Practical approach: use Auto ISO with an upper limit, and don’t be afraid to try ISO 6400 if the alternative is missing the shot. A noisy image is better than no image. Slight negative exposure compensation can help preserve the night look and avoid over-brightening shadows later.

Also adjust expectations and shoot what’s easier: corners or hairpins where cars are slower, moments in the pits/paddock, or intentional slower-shutter panning shots to show motion. Those are often more achievable than freezing fast action all around the track.

If you want the best chance of freezing on-track action at night, faster gear helps a lot—typically an f/2.8 lens and a camera body with stronger high-ISO performance.