Am I missing something ? A race track has finite width lanes for which you shoehorn the car thru a racing line path. This 'line' will be different for each of vehicle and tire parameter settings.
To be specific, is the data being shown here == 'THE LINE' or is it just a walk around the center of the track map ?
BTW: with a little handle graphics you can study the track mapping problems a bit better. I'd use radius because it relates to my sense of surveying, but here is curvature to be PC.
I needed a crutch to figure out where I was on the track.
track_curve.JPG