There was plenty of experimentation with tires in the 78 degree heat and increasing humidity under cloudy skies. Firestone’s guayule-sidewalled tires had a noticeable peak for one lap – two by the gentlest driver/car combinations – but drivers and race engineers still needed to know how long they could make them last in what will be a 100-lap race dominated by the primary tire.
Colton Herta, who will start from the outside of the front row alongside his Andretti Autosport teammate Romain Grosjean, was also seen experimenting with the inside line into the wide Turn 1. The paint on the runway of Albert Whitted Airport can make outbraking maneuvers particularly difficult, with rubber build-up off-line exacerbating the problem.
