Ganassi driver Scott Dixon set the fastest time in the final practice session for this weekend's IndyCar race at Texas Motor Speedway.
The New Zealander topped the timing screens with a best lap of 216.139mph, with A.J. Foyt's Mike Conway second-quickest at 215.340mph. Running time was cut a few minutes short after Takuma Sato's Rahal Letterman Lanigan car came to a stop on the track.
The session provided the teams with an opportunity to trial a late change to the cars' aero profile for the weekend after concerns from some drivers that too much downforce had been removed in an effort to cut out pack racing.
The series had mandated a maximum rear wing setting of minus five degrees going into the weekend, but after consultation with the drivers, tweaked the rules prior to qualifying to forbid the use of a gurney flap on the rear wing. While the change proved popular with some drivers, others were concerned that the change was a move too far in the other direction and made the car too unpredictable, leading the series to adopt a compromise solution of permitting the gurney flap to be reintroduced, but stipulating a maximum height of 1/8 inch.
Series officials predicted that the change would return a little more than half of the downforce that had been removed earlier in the day. The cars are still expected to be short of the downforce required to run an entire lap flat.